diff --git a/crates/example-types/src/auction_results_provider_types.rs b/crates/example-types/src/auction_results_provider_types.rs
index af2f8b7026..01978c1359 100644
--- a/crates/example-types/src/auction_results_provider_types.rs
+++ b/crates/example-types/src/auction_results_provider_types.rs
@@ -48,7 +48,7 @@ pub struct TestAuctionResultsProvider<TYPES: NodeType> {
 impl<TYPES: NodeType> AuctionResultsProvider<TYPES> for TestAuctionResultsProvider<TYPES> {
     /// Mock fetching the auction results, with optional error injection to simulate failure cases
     /// in the solver.
-    async fn fetch_auction_result(&self, view_number: TYPES::Time) -> Result<TYPES::AuctionResult> {
+    async fn fetch_auction_result(&self, view_number: TYPES::View) -> Result<TYPES::AuctionResult> {
         if let Some(url) = &self.broadcast_url {
             let resp =
                 reqwest::get(url.join(&format!("/v0/api/auction_results/{}", *view_number))?)
diff --git a/crates/example-types/src/node_types.rs b/crates/example-types/src/node_types.rs
index a8f06976c3..1ab2446c12 100644
--- a/crates/example-types/src/node_types.rs
+++ b/crates/example-types/src/node_types.rs
@@ -4,6 +4,12 @@
 // You should have received a copy of the MIT License
 // along with the HotShot repository. If not, see <https://mit-license.org/>.
 
+use crate::{
+    auction_results_provider_types::{TestAuctionResult, TestAuctionResultsProvider},
+    block_types::{TestBlockHeader, TestBlockPayload, TestTransaction},
+    state_types::{TestInstanceState, TestValidatedState},
+    storage_types::TestStorage,
+};
 use hotshot::traits::{
     election::{
         randomized_committee::RandomizedCommittee, static_committee::StaticCommittee,
@@ -12,6 +18,7 @@ use hotshot::traits::{
     implementations::{CombinedNetworks, Libp2pNetwork, MemoryNetwork, PushCdnNetwork},
     NodeImplementation,
 };
+use hotshot_types::data::EpochNumber;
 use hotshot_types::{
     data::ViewNumber,
     signature_key::{BLSPubKey, BuilderKey},
@@ -20,13 +27,6 @@ use hotshot_types::{
 use serde::{Deserialize, Serialize};
 use vbs::version::StaticVersion;
 
-use crate::{
-    auction_results_provider_types::{TestAuctionResult, TestAuctionResultsProvider},
-    block_types::{TestBlockHeader, TestBlockPayload, TestTransaction},
-    state_types::{TestInstanceState, TestValidatedState},
-    storage_types::TestStorage,
-};
-
 #[derive(
     Copy,
     Clone,
@@ -45,7 +45,8 @@ use crate::{
 pub struct TestTypes;
 impl NodeType for TestTypes {
     type AuctionResult = TestAuctionResult;
-    type Time = ViewNumber;
+    type View = ViewNumber;
+    type Epoch = EpochNumber;
     type BlockHeader = TestBlockHeader;
     type BlockPayload = TestBlockPayload;
     type SignatureKey = BLSPubKey;
@@ -74,7 +75,8 @@ impl NodeType for TestTypes {
 pub struct TestTypesRandomizedLeader;
 impl NodeType for TestTypesRandomizedLeader {
     type AuctionResult = TestAuctionResult;
-    type Time = ViewNumber;
+    type View = ViewNumber;
+    type Epoch = EpochNumber;
     type BlockHeader = TestBlockHeader;
     type BlockPayload = TestBlockPayload;
     type SignatureKey = BLSPubKey;
@@ -103,7 +105,8 @@ impl NodeType for TestTypesRandomizedLeader {
 pub struct TestConsecutiveLeaderTypes;
 impl NodeType for TestConsecutiveLeaderTypes {
     type AuctionResult = TestAuctionResult;
-    type Time = ViewNumber;
+    type View = ViewNumber;
+    type Epoch = EpochNumber;
     type BlockHeader = TestBlockHeader;
     type BlockPayload = TestBlockPayload;
     type SignatureKey = BLSPubKey;
@@ -235,8 +238,8 @@ mod tests {
 
         let data = TestData { data: 10 };
 
-        let view_0 = <TestTypes as NodeType>::Time::new(0);
-        let view_1 = <TestTypes as NodeType>::Time::new(1);
+        let view_0 = <TestTypes as NodeType>::View::new(0);
+        let view_1 = <TestTypes as NodeType>::View::new(1);
 
         let versioned_data_0 =
             VersionedVoteData::<TestTypes, TestData, MarketplaceTestVersions>::new(
diff --git a/crates/example-types/src/storage_types.rs b/crates/example-types/src/storage_types.rs
index 5c6277f35c..2a093b1f02 100644
--- a/crates/example-types/src/storage_types.rs
+++ b/crates/example-types/src/storage_types.rs
@@ -29,17 +29,17 @@ use hotshot_types::{
 use crate::testable_delay::{DelayConfig, SupportedTraitTypesForAsyncDelay, TestableDelay};
 
 type VidShares<TYPES> = HashMap<
-    <TYPES as NodeType>::Time,
+    <TYPES as NodeType>::View,
     HashMap<<TYPES as NodeType>::SignatureKey, Proposal<TYPES, VidDisperseShare<TYPES>>>,
 >;
 
 #[derive(Clone, Debug)]
 pub struct TestStorageState<TYPES: NodeType> {
     vids: VidShares<TYPES>,
-    das: HashMap<TYPES::Time, Proposal<TYPES, DaProposal<TYPES>>>,
-    proposals: BTreeMap<TYPES::Time, Proposal<TYPES, QuorumProposal<TYPES>>>,
+    das: HashMap<TYPES::View, Proposal<TYPES, DaProposal<TYPES>>>,
+    proposals: BTreeMap<TYPES::View, Proposal<TYPES, QuorumProposal<TYPES>>>,
     high_qc: Option<hotshot_types::simple_certificate::QuorumCertificate<TYPES>>,
-    action: TYPES::Time,
+    action: TYPES::View,
 }
 
 impl<TYPES: NodeType> Default for TestStorageState<TYPES> {
@@ -49,7 +49,7 @@ impl<TYPES: NodeType> Default for TestStorageState<TYPES> {
             das: HashMap::new(),
             proposals: BTreeMap::new(),
             high_qc: None,
-            action: TYPES::Time::genesis(),
+            action: TYPES::View::genesis(),
         }
     }
 }
@@ -87,7 +87,7 @@ impl<TYPES: NodeType> TestableDelay for TestStorage<TYPES> {
 impl<TYPES: NodeType> TestStorage<TYPES> {
     pub async fn proposals_cloned(
         &self,
-    ) -> BTreeMap<TYPES::Time, Proposal<TYPES, QuorumProposal<TYPES>>> {
+    ) -> BTreeMap<TYPES::View, Proposal<TYPES, QuorumProposal<TYPES>>> {
         self.inner.read().await.proposals.clone()
     }
     pub async fn high_qc_cloned(&self) -> Option<QuorumCertificate<TYPES>> {
@@ -96,7 +96,7 @@ impl<TYPES: NodeType> TestStorage<TYPES> {
     pub async fn decided_upgrade_certificate(&self) -> Option<UpgradeCertificate<TYPES>> {
         self.decided_upgrade_certificate.read().await.clone()
     }
-    pub async fn last_actioned_view(&self) -> TYPES::Time {
+    pub async fn last_actioned_view(&self) -> TYPES::View {
         self.inner.read().await.action
     }
 }
@@ -145,7 +145,7 @@ impl<TYPES: NodeType> Storage<TYPES> for TestStorage<TYPES> {
 
     async fn record_action(
         &self,
-        view: <TYPES as NodeType>::Time,
+        view: <TYPES as NodeType>::View,
         action: hotshot_types::event::HotShotAction,
     ) -> Result<()> {
         if self.should_return_err {
@@ -180,7 +180,7 @@ impl<TYPES: NodeType> Storage<TYPES> for TestStorage<TYPES> {
     async fn update_undecided_state(
         &self,
         _leafs: CommitmentMap<Leaf<TYPES>>,
-        _state: BTreeMap<TYPES::Time, View<TYPES>>,
+        _state: BTreeMap<TYPES::View, View<TYPES>>,
     ) -> Result<()> {
         if self.should_return_err {
             bail!("Failed to update high qc to storage");
diff --git a/crates/examples/infra/mod.rs b/crates/examples/infra/mod.rs
index 96072cce89..0c7e8db673 100755
--- a/crates/examples/infra/mod.rs
+++ b/crates/examples/infra/mod.rs
@@ -463,7 +463,7 @@ pub trait RunDa<
         let start = Instant::now();
 
         let mut event_stream = context.event_stream();
-        let mut anchor_view: TYPES::Time = <TYPES::Time as ConsensusTime>::genesis();
+        let mut anchor_view: TYPES::View = <TYPES::View as ConsensusTime>::genesis();
         let mut num_successful_commits = 0;
 
         context.hotshot.start_consensus().await;
@@ -563,7 +563,7 @@ pub trait RunDa<
             .hotshot
             .memberships
             .quorum_membership
-            .committee_leaders(TYPES::Time::genesis())
+            .committee_leaders(TYPES::View::genesis(), TYPES::Epoch::genesis())
             .len();
         let total_num_views = usize::try_from(consensus.locked_view().u64()).unwrap();
         // `failed_num_views` could include uncommitted views
diff --git a/crates/hotshot/src/lib.rs b/crates/hotshot/src/lib.rs
index 577318befb..bc2fbf8128 100644
--- a/crates/hotshot/src/lib.rs
+++ b/crates/hotshot/src/lib.rs
@@ -123,7 +123,7 @@ pub struct SystemContext<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versi
     instance_state: Arc<TYPES::InstanceState>,
 
     /// The view to enter when first starting consensus
-    start_view: TYPES::Time,
+    start_view: TYPES::View,
 
     /// Access to the output event stream.
     output_event_stream: (Sender<Event<TYPES>>, InactiveReceiver<Event<TYPES>>),
@@ -302,9 +302,17 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> SystemContext<T
             saved_payloads.insert(anchored_leaf.view_number(), Arc::clone(&encoded_txns));
         }
 
+        let anchored_epoch = if config.epoch_height == 0 {
+            TYPES::Epoch::new(0)
+        } else if anchored_leaf.height() % config.epoch_height == 0 {
+            TYPES::Epoch::new(anchored_leaf.height() / config.epoch_height)
+        } else {
+            TYPES::Epoch::new(anchored_leaf.height() / config.epoch_height + 1)
+        };
         let consensus = Consensus::new(
             validated_state_map,
             anchored_leaf.view_number(),
+            anchored_epoch,
             anchored_leaf.view_number(),
             anchored_leaf.view_number(),
             initializer.actioned_view,
@@ -391,7 +399,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> SystemContext<T
                 self.internal_event_stream
                     .0
                     .broadcast_direct(Arc::new(HotShotEvent::ValidatedStateUpdated(
-                        TYPES::Time::new(*self.start_view),
+                        TYPES::View::new(*self.start_view),
                         validated_state.clone(),
                     )))
                     .await
@@ -420,7 +428,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> SystemContext<T
         {
             // Some applications seem to expect a leaf decide event for the genesis leaf,
             // which contains only that leaf and nothing else.
-            if self.anchored_leaf.view_number() == TYPES::Time::genesis() {
+            if self.anchored_leaf.view_number() == TYPES::View::genesis() {
                 let (validated_state, state_delta) =
                     TYPES::ValidatedState::genesis(&self.instance_state);
 
@@ -558,7 +566,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> SystemContext<T
     /// [`decided_state`](Self::decided_state)) or if there is no path for the requested
     /// view to ever be decided.
     #[instrument(skip_all, target = "SystemContext", fields(id = self.id))]
-    pub async fn state(&self, view: TYPES::Time) -> Option<Arc<TYPES::ValidatedState>> {
+    pub async fn state(&self, view: TYPES::View) -> Option<Arc<TYPES::ValidatedState>> {
         self.consensus.read().await.state(view).cloned()
     }
 
@@ -964,10 +972,10 @@ pub struct HotShotInitializer<TYPES: NodeType> {
     state_delta: Option<Arc<<TYPES::ValidatedState as ValidatedState<TYPES>>::Delta>>,
 
     /// Starting view number that should be equivelant to the view the node shut down with last.
-    start_view: TYPES::Time,
+    start_view: TYPES::View,
     /// The view we last performed an action in.  An action is Proposing or voting for
     /// Either the quorum or DA.
-    actioned_view: TYPES::Time,
+    actioned_view: TYPES::View,
     /// Highest QC that was seen, for genesis it's the genesis QC.  It should be for a view greater
     /// than `inner`s view number for the non genesis case because we must have seen higher QCs
     /// to decide on the leaf.
@@ -978,9 +986,9 @@ pub struct HotShotInitializer<TYPES: NodeType> {
     /// to vote and propose right away if they didn't miss anything while down.
     undecided_leafs: Vec<Leaf<TYPES>>,
     /// Not yet decided state
-    undecided_state: BTreeMap<TYPES::Time, View<TYPES>>,
+    undecided_state: BTreeMap<TYPES::View, View<TYPES>>,
     /// Proposals we have sent out to provide to others for catchup
-    saved_proposals: BTreeMap<TYPES::Time, Proposal<TYPES, QuorumProposal<TYPES>>>,
+    saved_proposals: BTreeMap<TYPES::View, Proposal<TYPES, QuorumProposal<TYPES>>>,
 }
 
 impl<TYPES: NodeType> HotShotInitializer<TYPES> {
@@ -997,8 +1005,8 @@ impl<TYPES: NodeType> HotShotInitializer<TYPES> {
             inner: Leaf::genesis(&validated_state, &instance_state).await,
             validated_state: Some(Arc::new(validated_state)),
             state_delta: Some(Arc::new(state_delta)),
-            start_view: TYPES::Time::new(0),
-            actioned_view: TYPES::Time::new(0),
+            start_view: TYPES::View::new(0),
+            actioned_view: TYPES::View::new(0),
             saved_proposals: BTreeMap::new(),
             high_qc,
             decided_upgrade_certificate: None,
@@ -1020,13 +1028,13 @@ impl<TYPES: NodeType> HotShotInitializer<TYPES> {
         anchor_leaf: Leaf<TYPES>,
         instance_state: TYPES::InstanceState,
         validated_state: Option<Arc<TYPES::ValidatedState>>,
-        start_view: TYPES::Time,
-        actioned_view: TYPES::Time,
-        saved_proposals: BTreeMap<TYPES::Time, Proposal<TYPES, QuorumProposal<TYPES>>>,
+        start_view: TYPES::View,
+        actioned_view: TYPES::View,
+        saved_proposals: BTreeMap<TYPES::View, Proposal<TYPES, QuorumProposal<TYPES>>>,
         high_qc: QuorumCertificate<TYPES>,
         decided_upgrade_certificate: Option<UpgradeCertificate<TYPES>>,
         undecided_leafs: Vec<Leaf<TYPES>>,
-        undecided_state: BTreeMap<TYPES::Time, View<TYPES>>,
+        undecided_state: BTreeMap<TYPES::View, View<TYPES>>,
     ) -> Self {
         Self {
             inner: anchor_leaf,
diff --git a/crates/hotshot/src/tasks/mod.rs b/crates/hotshot/src/tasks/mod.rs
index 8433ed6121..0f89203f45 100644
--- a/crates/hotshot/src/tasks/mod.rs
+++ b/crates/hotshot/src/tasks/mod.rs
@@ -170,7 +170,8 @@ pub fn add_network_event_task<
 ) {
     let network_state: NetworkEventTaskState<_, V, _, _> = NetworkEventTaskState {
         network,
-        view: TYPES::Time::genesis(),
+        view: TYPES::View::genesis(),
+        epoch: TYPES::Epoch::genesis(),
         quorum_membership,
         da_membership,
         storage: Arc::clone(&handle.storage()),
diff --git a/crates/hotshot/src/tasks/task_state.rs b/crates/hotshot/src/tasks/task_state.rs
index 50d08221c4..d23799cc59 100644
--- a/crates/hotshot/src/tasks/task_state.rs
+++ b/crates/hotshot/src/tasks/task_state.rs
@@ -70,6 +70,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> CreateTaskState
         return Self {
             output_event_stream: handle.hotshot.external_event_stream.0.clone(),
             cur_view: handle.cur_view().await,
+            cur_epoch: handle.cur_epoch().await,
             quorum_membership: handle.hotshot.memberships.quorum_membership.clone().into(),
             network: Arc::clone(&handle.hotshot.network),
             vote_collectors: BTreeMap::default(),
@@ -91,6 +92,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> CreateTaskState
         return Self {
             output_event_stream: handle.hotshot.external_event_stream.0.clone(),
             cur_view: handle.cur_view().await,
+            cur_epoch: handle.cur_epoch().await,
             quorum_membership: handle.hotshot.memberships.quorum_membership.clone().into(),
             network: Arc::clone(&handle.hotshot.network),
             vote_collector: None.into(),
@@ -118,6 +120,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> CreateTaskState
         Self {
             consensus: OuterConsensus::new(handle.hotshot.consensus()),
             cur_view: handle.cur_view().await,
+            cur_epoch: handle.cur_epoch().await,
             vote_collector: None,
             network: Arc::clone(&handle.hotshot.network),
             membership: handle.hotshot.memberships.quorum_membership.clone().into(),
@@ -140,6 +143,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> CreateTaskState
             network: Arc::clone(&handle.hotshot.network),
             quorum_membership: handle.hotshot.memberships.quorum_membership.clone().into(),
             cur_view: handle.cur_view().await,
+            cur_epoch: handle.cur_epoch().await,
             vote_collectors: BTreeMap::default(),
             public_key: handle.public_key().clone(),
             private_key: handle.private_key().clone(),
@@ -160,6 +164,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> CreateTaskState
         Self {
             current_view: cur_view,
             next_view: cur_view,
+            current_epoch: handle.cur_epoch().await,
             network: Arc::clone(&handle.hotshot.network),
             membership: handle.hotshot.memberships.quorum_membership.clone().into(),
             public_key: handle.public_key().clone(),
@@ -171,7 +176,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> CreateTaskState
             finalize_relay_map: HashMap::default().into(),
             view_sync_timeout: handle.hotshot.config.view_sync_timeout,
             id: handle.hotshot.id,
-            last_garbage_collected_view: TYPES::Time::new(0),
+            last_garbage_collected_view: TYPES::View::new(0),
             upgrade_lock: handle.hotshot.upgrade_lock.clone(),
         }
     }
@@ -187,6 +192,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> CreateTaskState
             output_event_stream: handle.hotshot.external_event_stream.0.clone(),
             consensus: OuterConsensus::new(handle.hotshot.consensus()),
             cur_view: handle.cur_view().await,
+            cur_epoch: handle.cur_epoch().await,
             network: Arc::clone(&handle.hotshot.network),
             membership: handle.hotshot.memberships.quorum_membership.clone().into(),
             public_key: handle.public_key().clone(),
@@ -280,6 +286,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> CreateTaskState
             consensus: OuterConsensus::new(consensus),
             cur_view: handle.cur_view().await,
             cur_view_time: Utc::now().timestamp(),
+            cur_epoch: handle.cur_epoch().await,
             network: Arc::clone(&handle.hotshot.network),
             quorum_membership: handle.hotshot.memberships.quorum_membership.clone().into(),
             timeout_membership: handle.hotshot.memberships.quorum_membership.clone().into(),
@@ -317,6 +324,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> CreateTaskState
             storage: Arc::clone(&handle.storage),
             cur_view: handle.cur_view().await,
             cur_view_time: Utc::now().timestamp(),
+            cur_epoch: handle.cur_epoch().await,
             output_event_stream: handle.hotshot.external_event_stream.0.clone(),
             timeout_task: async_spawn(async {}),
             timeout: handle.hotshot.config.next_view_timeout,
diff --git a/crates/hotshot/src/traits/election/randomized_committee.rs b/crates/hotshot/src/traits/election/randomized_committee.rs
index b761eb1ee2..4fed098e9c 100644
--- a/crates/hotshot/src/traits/election/randomized_committee.rs
+++ b/crates/hotshot/src/traits/election/randomized_committee.rs
@@ -82,6 +82,7 @@ impl<TYPES: NodeType> Membership<TYPES> for RandomizedCommittee<TYPES> {
     /// Get the stake table for the current view
     fn stake_table(
         &self,
+        _epoch: <TYPES as NodeType>::Epoch,
     ) -> Vec<<<TYPES as NodeType>::SignatureKey as SignatureKey>::StakeTableEntry> {
         self.stake_table.clone()
     }
@@ -89,7 +90,8 @@ impl<TYPES: NodeType> Membership<TYPES> for RandomizedCommittee<TYPES> {
     /// Get all members of the committee for the current view
     fn committee_members(
         &self,
-        _view_number: <TYPES as NodeType>::Time,
+        _view_number: <TYPES as NodeType>::View,
+        _epoch: <TYPES as NodeType>::Epoch,
     ) -> std::collections::BTreeSet<<TYPES as NodeType>::SignatureKey> {
         self.stake_table
             .iter()
@@ -100,7 +102,8 @@ impl<TYPES: NodeType> Membership<TYPES> for RandomizedCommittee<TYPES> {
     /// Get all eligible leaders of the committee for the current view
     fn committee_leaders(
         &self,
-        _view_number: <TYPES as NodeType>::Time,
+        _view_number: <TYPES as NodeType>::View,
+        _epoch: <TYPES as NodeType>::Epoch,
     ) -> std::collections::BTreeSet<<TYPES as NodeType>::SignatureKey> {
         self.eligible_leaders
             .iter()
@@ -112,13 +115,18 @@ impl<TYPES: NodeType> Membership<TYPES> for RandomizedCommittee<TYPES> {
     fn stake(
         &self,
         pub_key: &<TYPES as NodeType>::SignatureKey,
+        _epoch: <TYPES as NodeType>::Epoch,
     ) -> Option<<TYPES::SignatureKey as SignatureKey>::StakeTableEntry> {
         // Only return the stake if it is above zero
         self.indexed_stake_table.get(pub_key).cloned()
     }
 
     /// Check if a node has stake in the committee
-    fn has_stake(&self, pub_key: &<TYPES as NodeType>::SignatureKey) -> bool {
+    fn has_stake(
+        &self,
+        pub_key: &<TYPES as NodeType>::SignatureKey,
+        _epoch: <TYPES as NodeType>::Epoch,
+    ) -> bool {
         self.indexed_stake_table
             .get(pub_key)
             .is_some_and(|x| x.stake() > U256::zero())
@@ -130,7 +138,11 @@ impl<TYPES: NodeType> Membership<TYPES> for RandomizedCommittee<TYPES> {
     }
 
     /// Index the vector of public keys with the current view number
-    fn leader(&self, view_number: TYPES::Time) -> TYPES::SignatureKey {
+    fn leader(
+        &self,
+        view_number: TYPES::View,
+        _epoch: <TYPES as NodeType>::Epoch,
+    ) -> TYPES::SignatureKey {
         let mut rng: StdRng = rand::SeedableRng::seed_from_u64(*view_number);
 
         let randomized_view_number: u64 = rng.gen_range(0..=u64::MAX);
@@ -143,7 +155,7 @@ impl<TYPES: NodeType> Membership<TYPES> for RandomizedCommittee<TYPES> {
     }
 
     /// Get the total number of nodes in the committee
-    fn total_nodes(&self) -> usize {
+    fn total_nodes(&self, _epoch: <TYPES as NodeType>::Epoch) -> usize {
         self.stake_table.len()
     }
 
diff --git a/crates/hotshot/src/traits/election/static_committee.rs b/crates/hotshot/src/traits/election/static_committee.rs
index 69cc5ce9c2..2ef52a66e2 100644
--- a/crates/hotshot/src/traits/election/static_committee.rs
+++ b/crates/hotshot/src/traits/election/static_committee.rs
@@ -80,6 +80,7 @@ impl<TYPES: NodeType> Membership<TYPES> for StaticCommittee<TYPES> {
     /// Get the stake table for the current view
     fn stake_table(
         &self,
+        _epoch: <TYPES as NodeType>::Epoch,
     ) -> Vec<<<TYPES as NodeType>::SignatureKey as SignatureKey>::StakeTableEntry> {
         self.stake_table.clone()
     }
@@ -87,7 +88,8 @@ impl<TYPES: NodeType> Membership<TYPES> for StaticCommittee<TYPES> {
     /// Get all members of the committee for the current view
     fn committee_members(
         &self,
-        _view_number: <TYPES as NodeType>::Time,
+        _view_number: <TYPES as NodeType>::View,
+        _epoch: <TYPES as NodeType>::Epoch,
     ) -> std::collections::BTreeSet<<TYPES as NodeType>::SignatureKey> {
         self.stake_table
             .iter()
@@ -98,7 +100,8 @@ impl<TYPES: NodeType> Membership<TYPES> for StaticCommittee<TYPES> {
     /// Get all eligible leaders of the committee for the current view
     fn committee_leaders(
         &self,
-        _view_number: <TYPES as NodeType>::Time,
+        _view_number: <TYPES as NodeType>::View,
+        _epoch: <TYPES as NodeType>::Epoch,
     ) -> std::collections::BTreeSet<<TYPES as NodeType>::SignatureKey> {
         self.eligible_leaders
             .iter()
@@ -110,13 +113,18 @@ impl<TYPES: NodeType> Membership<TYPES> for StaticCommittee<TYPES> {
     fn stake(
         &self,
         pub_key: &<TYPES as NodeType>::SignatureKey,
+        _epoch: <TYPES as NodeType>::Epoch,
     ) -> Option<<TYPES::SignatureKey as SignatureKey>::StakeTableEntry> {
         // Only return the stake if it is above zero
         self.indexed_stake_table.get(pub_key).cloned()
     }
 
     /// Check if a node has stake in the committee
-    fn has_stake(&self, pub_key: &<TYPES as NodeType>::SignatureKey) -> bool {
+    fn has_stake(
+        &self,
+        pub_key: &<TYPES as NodeType>::SignatureKey,
+        _epoch: <TYPES as NodeType>::Epoch,
+    ) -> bool {
         self.indexed_stake_table
             .get(pub_key)
             .is_some_and(|x| x.stake() > U256::zero())
@@ -128,7 +136,11 @@ impl<TYPES: NodeType> Membership<TYPES> for StaticCommittee<TYPES> {
     }
 
     /// Index the vector of public keys with the current view number
-    fn leader(&self, view_number: TYPES::Time) -> TYPES::SignatureKey {
+    fn leader(
+        &self,
+        view_number: TYPES::View,
+        _epoch: <TYPES as NodeType>::Epoch,
+    ) -> TYPES::SignatureKey {
         #[allow(clippy::cast_possible_truncation)]
         let index = *view_number as usize % self.eligible_leaders.len();
         let res = self.eligible_leaders[index].clone();
@@ -136,7 +148,7 @@ impl<TYPES: NodeType> Membership<TYPES> for StaticCommittee<TYPES> {
     }
 
     /// Get the total number of nodes in the committee
-    fn total_nodes(&self) -> usize {
+    fn total_nodes(&self, _epoch: <TYPES as NodeType>::Epoch) -> usize {
         self.stake_table.len()
     }
 
diff --git a/crates/hotshot/src/traits/election/static_committee_leader_two_views.rs b/crates/hotshot/src/traits/election/static_committee_leader_two_views.rs
index 9ce83c14a0..db41aad2ab 100644
--- a/crates/hotshot/src/traits/election/static_committee_leader_two_views.rs
+++ b/crates/hotshot/src/traits/election/static_committee_leader_two_views.rs
@@ -80,6 +80,7 @@ impl<TYPES: NodeType> Membership<TYPES> for StaticCommitteeLeaderForTwoViews<TYP
     /// Get the stake table for the current view
     fn stake_table(
         &self,
+        _epoch: <TYPES as NodeType>::Epoch,
     ) -> Vec<<<TYPES as NodeType>::SignatureKey as SignatureKey>::StakeTableEntry> {
         self.stake_table.clone()
     }
@@ -87,7 +88,8 @@ impl<TYPES: NodeType> Membership<TYPES> for StaticCommitteeLeaderForTwoViews<TYP
     /// Get all members of the committee for the current view
     fn committee_members(
         &self,
-        _view_number: <TYPES as NodeType>::Time,
+        _view_number: <TYPES as NodeType>::View,
+        _epoch: <TYPES as NodeType>::Epoch,
     ) -> std::collections::BTreeSet<<TYPES as NodeType>::SignatureKey> {
         self.stake_table
             .iter()
@@ -98,7 +100,8 @@ impl<TYPES: NodeType> Membership<TYPES> for StaticCommitteeLeaderForTwoViews<TYP
     /// Get all eligible leaders of the committee for the current view
     fn committee_leaders(
         &self,
-        _view_number: <TYPES as NodeType>::Time,
+        _view_number: <TYPES as NodeType>::View,
+        _epoch: <TYPES as NodeType>::Epoch,
     ) -> std::collections::BTreeSet<<TYPES as NodeType>::SignatureKey> {
         self.eligible_leaders
             .iter()
@@ -110,13 +113,18 @@ impl<TYPES: NodeType> Membership<TYPES> for StaticCommitteeLeaderForTwoViews<TYP
     fn stake(
         &self,
         pub_key: &<TYPES as NodeType>::SignatureKey,
+        _epoch: <TYPES as NodeType>::Epoch,
     ) -> Option<<TYPES::SignatureKey as SignatureKey>::StakeTableEntry> {
         // Only return the stake if it is above zero
         self.indexed_stake_table.get(pub_key).cloned()
     }
 
     /// Check if a node has stake in the committee
-    fn has_stake(&self, pub_key: &<TYPES as NodeType>::SignatureKey) -> bool {
+    fn has_stake(
+        &self,
+        pub_key: &<TYPES as NodeType>::SignatureKey,
+        _epoch: <TYPES as NodeType>::Epoch,
+    ) -> bool {
         self.indexed_stake_table
             .get(pub_key)
             .is_some_and(|x| x.stake() > U256::zero())
@@ -128,7 +136,11 @@ impl<TYPES: NodeType> Membership<TYPES> for StaticCommitteeLeaderForTwoViews<TYP
     }
 
     /// Index the vector of public keys with the current view number
-    fn leader(&self, view_number: TYPES::Time) -> TYPES::SignatureKey {
+    fn leader(
+        &self,
+        view_number: TYPES::View,
+        _epoch: <TYPES as NodeType>::Epoch,
+    ) -> TYPES::SignatureKey {
         let index =
             usize::try_from((*view_number / 2) % self.eligible_leaders.len() as u64).unwrap();
         let res = self.eligible_leaders[index].clone();
@@ -136,7 +148,7 @@ impl<TYPES: NodeType> Membership<TYPES> for StaticCommitteeLeaderForTwoViews<TYP
     }
 
     /// Get the total number of nodes in the committee
-    fn total_nodes(&self) -> usize {
+    fn total_nodes(&self, _epoch: <TYPES as NodeType>::Epoch) -> usize {
         self.stake_table.len()
     }
 
diff --git a/crates/hotshot/src/traits/networking/combined_network.rs b/crates/hotshot/src/traits/networking/combined_network.rs
index 2bb7eba49c..002f5d543c 100644
--- a/crates/hotshot/src/traits/networking/combined_network.rs
+++ b/crates/hotshot/src/traits/networking/combined_network.rs
@@ -484,7 +484,7 @@ impl<TYPES: NodeType> ConnectedNetwork<TYPES::SignatureKey> for CombinedNetworks
         self.secondary().queue_node_lookup(view_number, pk)
     }
 
-    async fn update_view<'a, T>(&'a self, view: u64, membership: &T::Membership)
+    async fn update_view<'a, T>(&'a self, view: u64, epoch: u64, membership: &T::Membership)
     where
         T: NodeType<SignatureKey = TYPES::SignatureKey> + 'a,
     {
@@ -505,7 +505,10 @@ impl<TYPES: NodeType> ConnectedNetwork<TYPES::SignatureKey> for CombinedNetworks
             }
         });
         // Run `update_view` logic for the libp2p network
-        self.networks.1.update_view::<T>(view, membership).await;
+        self.networks
+            .1
+            .update_view::<T>(view, epoch, membership)
+            .await;
     }
 
     fn is_primary_down(&self) -> bool {
diff --git a/crates/hotshot/src/traits/networking/libp2p_network.rs b/crates/hotshot/src/traits/networking/libp2p_network.rs
index 32551fba72..d25fc91762 100644
--- a/crates/hotshot/src/traits/networking/libp2p_network.rs
+++ b/crates/hotshot/src/traits/networking/libp2p_network.rs
@@ -1019,12 +1019,13 @@ impl<K: SignatureKey + 'static> ConnectedNetwork<K> for Libp2pNetwork<K> {
     /// So the logic with libp2p is to prefetch upcomming leaders libp2p address to
     /// save time when we later need to direct message the leader our vote. Hence the
     /// use of the future view and leader to queue the lookups.
-    async fn update_view<'a, TYPES>(&'a self, view: u64, membership: &TYPES::Membership)
+    async fn update_view<'a, TYPES>(&'a self, view: u64, epoch: u64, membership: &TYPES::Membership)
     where
         TYPES: NodeType<SignatureKey = K> + 'a,
     {
-        let future_view = <TYPES as NodeType>::Time::new(view) + LOOK_AHEAD;
-        let future_leader = membership.leader(future_view);
+        let future_view = <TYPES as NodeType>::View::new(view) + LOOK_AHEAD;
+        let epoch = <TYPES as NodeType>::Epoch::new(epoch);
+        let future_leader = membership.leader(future_view, epoch);
 
         let _ = self
             .queue_node_lookup(ViewNumber::new(*future_view), future_leader)
diff --git a/crates/hotshot/src/types/handle.rs b/crates/hotshot/src/types/handle.rs
index 5945e31ceb..cf6c8ffe02 100644
--- a/crates/hotshot/src/types/handle.rs
+++ b/crates/hotshot/src/types/handle.rs
@@ -136,7 +136,8 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES> + 'static, V: Versions>
     /// Errors if signing the request for proposal fails
     pub fn request_proposal(
         &self,
-        view: TYPES::Time,
+        view: TYPES::View,
+        epoch: TYPES::Epoch,
         leaf_commitment: Commitment<Leaf<TYPES>>,
     ) -> Result<impl futures::Future<Output = Result<Proposal<TYPES, QuorumProposal<TYPES>>>>> {
         // We need to be able to sign this request before submitting it to the network. Compute the
@@ -185,7 +186,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES> + 'static, V: Versions>
                 {
                     // Make sure that the quorum_proposal is valid
                     if let Err(err) = quorum_proposal
-                        .validate_signature(&mem, &upgrade_lock)
+                        .validate_signature(&mem, epoch, &upgrade_lock)
                         .await
                     {
                         tracing::warn!("Invalid Proposal Received after Request.  Err {:?}", err);
@@ -242,7 +243,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES> + 'static, V: Versions>
     /// return [`None`] if the requested view has already been decided (but see
     /// [`decided_state`](Self::decided_state)) or if there is no path for the requested
     /// view to ever be decided.
-    pub async fn state(&self, view: TYPES::Time) -> Option<Arc<TYPES::ValidatedState>> {
+    pub async fn state(&self, view: TYPES::View) -> Option<Arc<TYPES::ValidatedState>> {
         self.hotshot.state(view).await
     }
 
@@ -315,11 +316,15 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES> + 'static, V: Versions>
 
     /// Wrapper for `HotShotConsensusApi`'s `leader` function
     #[allow(clippy::unused_async)] // async for API compatibility reasons
-    pub async fn leader(&self, view_number: TYPES::Time) -> TYPES::SignatureKey {
+    pub async fn leader(
+        &self,
+        view_number: TYPES::View,
+        epoch_number: TYPES::Epoch,
+    ) -> TYPES::SignatureKey {
         self.hotshot
             .memberships
             .quorum_membership
-            .leader(view_number)
+            .leader(view_number, epoch_number)
     }
 
     // Below is for testing only:
@@ -346,10 +351,16 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES> + 'static, V: Versions>
 
     /// Wrapper to get the view number this node is on.
     #[instrument(skip_all, target = "SystemContextHandle", fields(id = self.hotshot.id))]
-    pub async fn cur_view(&self) -> TYPES::Time {
+    pub async fn cur_view(&self) -> TYPES::View {
         self.hotshot.consensus.read().await.cur_view()
     }
 
+    /// Wrapper to get the epoch number this node is on.
+    #[instrument(skip_all, target = "SystemContextHandle", fields(id = self.hotshot.id))]
+    pub async fn cur_epoch(&self) -> TYPES::Epoch {
+        self.hotshot.consensus.read().await.cur_epoch()
+    }
+
     /// Provides a reference to the underlying storage for this [`SystemContext`], allowing access to
     /// historical data
     #[must_use]
diff --git a/crates/orchestrator/run-config.toml b/crates/orchestrator/run-config.toml
index 909a6043b0..d1fecc10c9 100644
--- a/crates/orchestrator/run-config.toml
+++ b/crates/orchestrator/run-config.toml
@@ -38,6 +38,7 @@ timeout_ratio = [11, 10]
 round_start_delay = 1
 start_delay = 1
 num_bootstrap = 5
+epoch_height = 0
 
 [random_builder]
 txn_in_block = 100
diff --git a/crates/task-impls/src/consensus/handlers.rs b/crates/task-impls/src/consensus/handlers.rs
index cc0fa65a41..fec58d8409 100644
--- a/crates/task-impls/src/consensus/handlers.rs
+++ b/crates/task-impls/src/consensus/handlers.rs
@@ -42,7 +42,10 @@ pub(crate) async fn handle_quorum_vote_recv<
 ) -> Result<()> {
     // Are we the leader for this view?
     ensure!(
-        task_state.quorum_membership.leader(vote.view_number() + 1) == task_state.public_key,
+        task_state
+            .quorum_membership
+            .leader(vote.view_number() + 1, task_state.cur_epoch)
+            == task_state.public_key,
         format!(
             "We are not the leader for view {:?}",
             vote.view_number() + 1
@@ -54,6 +57,7 @@ pub(crate) async fn handle_quorum_vote_recv<
         vote,
         task_state.public_key.clone(),
         &task_state.quorum_membership,
+        task_state.cur_epoch,
         task_state.id,
         &event,
         sender,
@@ -77,7 +81,10 @@ pub(crate) async fn handle_timeout_vote_recv<
 ) -> Result<()> {
     // Are we the leader for this view?
     ensure!(
-        task_state.timeout_membership.leader(vote.view_number() + 1) == task_state.public_key,
+        task_state
+            .timeout_membership
+            .leader(vote.view_number() + 1, task_state.cur_epoch)
+            == task_state.public_key,
         format!(
             "We are not the leader for view {:?}",
             vote.view_number() + 1
@@ -89,6 +96,7 @@ pub(crate) async fn handle_timeout_vote_recv<
         vote,
         task_state.public_key.clone(),
         &task_state.quorum_membership,
+        task_state.cur_epoch,
         task_state.id,
         &event,
         sender,
@@ -106,7 +114,7 @@ pub(crate) async fn handle_view_change<
     I: NodeImplementation<TYPES>,
     V: Versions,
 >(
-    new_view_number: TYPES::Time,
+    new_view_number: TYPES::View,
     sender: &Sender<Arc<HotShotEvent<TYPES>>>,
     task_state: &mut ConsensusTaskState<TYPES, I, V>,
 ) -> Result<()> {
@@ -147,7 +155,7 @@ pub(crate) async fn handle_view_change<
         async move {
             async_sleep(Duration::from_millis(timeout)).await;
             broadcast_event(
-                Arc::new(HotShotEvent::Timeout(TYPES::Time::new(*view_number))),
+                Arc::new(HotShotEvent::Timeout(TYPES::View::new(*view_number))),
                 &stream,
             )
             .await;
@@ -167,7 +175,11 @@ pub(crate) async fn handle_view_change<
         .current_view
         .set(usize::try_from(task_state.cur_view.u64()).unwrap());
     let cur_view_time = Utc::now().timestamp();
-    if task_state.quorum_membership.leader(old_view_number) == task_state.public_key {
+    if task_state
+        .quorum_membership
+        .leader(old_view_number, task_state.cur_epoch)
+        == task_state.public_key
+    {
         #[allow(clippy::cast_precision_loss)]
         consensus
             .metrics
@@ -203,7 +215,7 @@ pub(crate) async fn handle_view_change<
 /// Handle a `Timeout` event.
 #[instrument(skip_all)]
 pub(crate) async fn handle_timeout<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>(
-    view_number: TYPES::Time,
+    view_number: TYPES::View,
     sender: &Sender<Arc<HotShotEvent<TYPES>>>,
     task_state: &mut ConsensusTaskState<TYPES, I, V>,
 ) -> Result<()> {
@@ -215,7 +227,7 @@ pub(crate) async fn handle_timeout<TYPES: NodeType, I: NodeImplementation<TYPES>
     ensure!(
         task_state
             .timeout_membership
-            .has_stake(&task_state.public_key),
+            .has_stake(&task_state.public_key, task_state.cur_epoch),
         format!("We were not chosen for the consensus committee for view {view_number:?}")
     );
 
@@ -260,7 +272,11 @@ pub(crate) async fn handle_timeout<TYPES: NodeType, I: NodeImplementation<TYPES>
         .metrics
         .number_of_timeouts
         .add(1);
-    if task_state.quorum_membership.leader(view_number) == task_state.public_key {
+    if task_state
+        .quorum_membership
+        .leader(view_number, task_state.cur_epoch)
+        == task_state.public_key
+    {
         task_state
             .consensus
             .read()
diff --git a/crates/task-impls/src/consensus/mod.rs b/crates/task-impls/src/consensus/mod.rs
index 82610978a6..fb1ec86fca 100644
--- a/crates/task-impls/src/consensus/mod.rs
+++ b/crates/task-impls/src/consensus/mod.rs
@@ -70,11 +70,14 @@ pub struct ConsensusTaskState<TYPES: NodeType, I: NodeImplementation<TYPES>, V:
     pub storage: Arc<RwLock<I::Storage>>,
 
     /// The view number that this node is currently executing in.
-    pub cur_view: TYPES::Time,
+    pub cur_view: TYPES::View,
 
     /// Timestamp this view starts at.
     pub cur_view_time: i64,
 
+    /// The epoch number that this node is currently executing in.
+    pub cur_epoch: TYPES::Epoch,
+
     /// Output events to application
     pub output_event_stream: async_broadcast::Sender<Event<TYPES>>,
 
@@ -88,7 +91,7 @@ pub struct ConsensusTaskState<TYPES: NodeType, I: NodeImplementation<TYPES>, V:
     pub consensus: OuterConsensus<TYPES>,
 
     /// The last decided view
-    pub last_decided_view: TYPES::Time,
+    pub last_decided_view: TYPES::View,
 
     /// The node's id
     pub id: u64,
diff --git a/crates/task-impls/src/da.rs b/crates/task-impls/src/da.rs
index 0189e20d41..2e7c1357ff 100644
--- a/crates/task-impls/src/da.rs
+++ b/crates/task-impls/src/da.rs
@@ -49,7 +49,10 @@ pub struct DaTaskState<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Version
     pub output_event_stream: async_broadcast::Sender<Event<TYPES>>,
 
     /// View number this view is executing in.
-    pub cur_view: TYPES::Time,
+    pub cur_view: TYPES::View,
+
+    /// Epoch number this node is executing in.
+    pub cur_epoch: TYPES::Epoch,
 
     /// Reference to consensus. Leader will require a read lock on this.
     pub consensus: OuterConsensus<TYPES>,
@@ -108,7 +111,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> DaTaskState<TYP
                 // the `DaProposalRecv` event. Otherwise, the view number subtraction below will
                 // cause an overflow error.
                 // TODO ED Come back to this - we probably don't need this, but we should also never receive a DAC where this fails, investigate block ready so it doesn't make one for the genesis block
-                if self.cur_view != TYPES::Time::genesis() && view < self.cur_view - 1 {
+                if self.cur_view != TYPES::View::genesis() && view < self.cur_view - 1 {
                     warn!("Throwing away DA proposal that is more than one view older");
                     return None;
                 }
@@ -127,7 +130,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> DaTaskState<TYP
                 let encoded_transactions_hash = Sha256::digest(&proposal.data.encoded_transactions);
 
                 // ED Is this the right leader?
-                let view_leader_key = self.da_membership.leader(view);
+                let view_leader_key = self.da_membership.leader(view, self.cur_epoch);
                 if view_leader_key != sender {
                     error!("DA proposal doesn't have expected leader key for view {} \n DA proposal is: {:?}", *view, proposal.data.clone());
                     return None;
@@ -163,7 +166,10 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> DaTaskState<TYP
                 )
                 .await;
 
-                if !self.da_membership.has_stake(&self.public_key) {
+                if !self
+                    .da_membership
+                    .has_stake(&self.public_key, self.cur_epoch)
+                {
                     debug!(
                         "We were not chosen for consensus committee on {:?}",
                         self.cur_view
@@ -178,7 +184,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> DaTaskState<TYP
                     return None;
                 }
                 let txns = Arc::clone(&proposal.data.encoded_transactions);
-                let num_nodes = self.quorum_membership.total_nodes();
+                let num_nodes = self.quorum_membership.total_nodes(self.cur_epoch);
                 let payload_commitment =
                     spawn_blocking(move || vid_commitment(&txns, num_nodes)).await;
                 #[cfg(async_executor_impl = "tokio")]
@@ -229,12 +235,14 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> DaTaskState<TYP
                     let pk = self.private_key.clone();
                     let public_key = self.public_key.clone();
                     let chan = event_stream.clone();
+                    let current_epoch = self.cur_epoch;
                     async_spawn(async move {
                         Consensus::calculate_and_update_vid(
                             OuterConsensus::new(Arc::clone(&consensus.inner_consensus)),
                             view_number,
                             membership,
                             &pk,
+                            current_epoch,
                         )
                         .await;
                         if let Some(Some(vid_share)) = consensus
@@ -260,8 +268,8 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> DaTaskState<TYP
                 debug!("DA vote recv, Main Task {:?}", vote.view_number());
                 // Check if we are the leader and the vote is from the sender.
                 let view = vote.view_number();
-                if self.da_membership.leader(view) != self.public_key {
-                    error!("We are not the DA committee leader for view {} are we leader for next view? {}", *view, self.da_membership.leader(view + 1) == self.public_key);
+                if self.da_membership.leader(view, self.cur_epoch) != self.public_key {
+                    error!("We are not the DA committee leader for view {} are we leader for next view? {}", *view, self.da_membership.leader(view + 1, self.cur_epoch) == self.public_key);
                     return None;
                 }
 
@@ -270,6 +278,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> DaTaskState<TYP
                     vote,
                     self.public_key.clone(),
                     &self.da_membership,
+                    self.cur_epoch,
                     self.id,
                     &event,
                     &event_stream,
@@ -289,7 +298,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> DaTaskState<TYP
                 self.cur_view = view;
 
                 // If we are not the next leader (DA leader for this view) immediately exit
-                if self.da_membership.leader(self.cur_view + 1) != self.public_key {
+                if self.da_membership.leader(self.cur_view + 1, self.cur_epoch) != self.public_key {
                     return None;
                 }
                 debug!("Polling for DA votes for view {}", *self.cur_view + 1);
diff --git a/crates/task-impls/src/events.rs b/crates/task-impls/src/events.rs
index f2ddb92ceb..8fc85a6031 100644
--- a/crates/task-impls/src/events.rs
+++ b/crates/task-impls/src/events.rs
@@ -47,7 +47,7 @@ impl<TYPES: NodeType> TaskEvent for HotShotEvent<TYPES> {
 #[derive(Debug, Clone)]
 pub struct ProposalMissing<TYPES: NodeType> {
     /// View of missing proposal
-    pub view: TYPES::Time,
+    pub view: TYPES::View,
     /// Channel to send the response back to
     pub response_chan: Sender<Option<Proposal<TYPES, QuorumProposal<TYPES>>>>,
 }
@@ -93,7 +93,7 @@ pub enum HotShotEvent<TYPES: NodeType> {
     /// Send a quorum vote to the next leader; emitted by a replica in the consensus task after seeing a valid quorum proposal
     QuorumVoteSend(QuorumVote<TYPES>),
     /// All dependencies for the quorum vote are validated.
-    QuorumVoteDependenciesValidated(TYPES::Time),
+    QuorumVoteDependenciesValidated(TYPES::View),
     /// A quorum proposal with the given parent leaf is validated.
     /// The full validation checks include:
     /// 1. The proposal is not for an old view
@@ -124,9 +124,9 @@ pub enum HotShotEvent<TYPES: NodeType> {
     /// The DA leader has collected enough votes to form a DAC; emitted by the DA leader in the DA task; sent to the entire network via the networking task
     DacSend(DaCertificate<TYPES>, TYPES::SignatureKey),
     /// The current view has changed; emitted by the replica in the consensus task or replica in the view sync task; received by almost all other tasks
-    ViewChange(TYPES::Time),
+    ViewChange(TYPES::View),
     /// Timeout for the view sync protocol; emitted by a replica in the view sync task
-    ViewSyncTimeout(TYPES::Time, u64, ViewSyncPhase),
+    ViewSyncTimeout(TYPES::View, u64, ViewSyncPhase),
 
     /// Receive a `ViewSyncPreCommitVote` from the network; received by a relay in the view sync task
     ViewSyncPreCommitVoteRecv(ViewSyncPreCommitVote<TYPES>),
@@ -157,9 +157,9 @@ pub enum HotShotEvent<TYPES: NodeType> {
     ViewSyncFinalizeCertificate2Send(ViewSyncFinalizeCertificate2<TYPES>, TYPES::SignatureKey),
 
     /// Trigger the start of the view sync protocol; emitted by view sync task; internal trigger only
-    ViewSyncTrigger(TYPES::Time),
+    ViewSyncTrigger(TYPES::View),
     /// A consensus view has timed out; emitted by a replica in the consensus task; received by the view sync task; internal event only
-    Timeout(TYPES::Time),
+    Timeout(TYPES::View),
     /// Receive transactions from the network
     TransactionsRecv(Vec<TYPES::Transaction>),
     /// Send transactions to the network
@@ -169,14 +169,14 @@ pub enum HotShotEvent<TYPES: NodeType> {
         VidCommitment,
         BuilderCommitment,
         <TYPES::BlockPayload as BlockPayload<TYPES>>::Metadata,
-        TYPES::Time,
+        TYPES::View,
         Vec1<BuilderFee<TYPES>>,
         Option<TYPES::AuctionResult>,
     ),
     /// Event when the transactions task has sequenced transactions. Contains the encoded transactions, the metadata, and the view number
     BlockRecv(PackedBundle<TYPES>),
     /// Event when the transactions task has a block formed
-    BlockReady(VidDisperse<TYPES>, TYPES::Time),
+    BlockReady(VidDisperse<TYPES>, TYPES::View),
     /// Event when consensus decided on a leaf
     LeafDecided(Vec<Leaf<TYPES>>),
     /// Send VID shares to VID storage nodes; emitted by the DA leader
@@ -205,13 +205,13 @@ pub enum HotShotEvent<TYPES: NodeType> {
 
     /* Consensus State Update Events */
     /// A undecided view has been created and added to the validated state storage.
-    ValidatedStateUpdated(TYPES::Time, View<TYPES>),
+    ValidatedStateUpdated(TYPES::View, View<TYPES>),
 
     /// A new locked view has been created (2-chain)
-    LockedViewUpdated(TYPES::Time),
+    LockedViewUpdated(TYPES::View),
 
     /// A new anchor view has been successfully reached by this node (3-chain).
-    LastDecidedViewUpdated(TYPES::Time),
+    LastDecidedViewUpdated(TYPES::View),
 
     /// A new high_qc has been reached by this node.
     UpdateHighQc(QuorumCertificate<TYPES>),
@@ -260,7 +260,7 @@ pub enum HotShotEvent<TYPES: NodeType> {
 impl<TYPES: NodeType> HotShotEvent<TYPES> {
     #[allow(clippy::too_many_lines)]
     /// Return the view number for a hotshot event if present
-    pub fn view_number(&self) -> Option<TYPES::Time> {
+    pub fn view_number(&self) -> Option<TYPES::View> {
         match self {
             HotShotEvent::QuorumVoteRecv(v) => Some(v.view_number()),
             HotShotEvent::TimeoutVoteRecv(v) | HotShotEvent::TimeoutVoteSend(v) => {
@@ -512,7 +512,7 @@ impl<TYPES: NodeType> Display for HotShotEvent<TYPES> {
                 write!(f, "BlockReady(view_number={view_number:?})")
             }
             HotShotEvent::LeafDecided(leaves) => {
-                let view_numbers: Vec<<TYPES as NodeType>::Time> =
+                let view_numbers: Vec<<TYPES as NodeType>::View> =
                     leaves.iter().map(Leaf::view_number).collect();
                 write!(f, "LeafDecided({view_numbers:?})")
             }
diff --git a/crates/task-impls/src/helpers.rs b/crates/task-impls/src/helpers.rs
index 5df8200f16..cd4bf5b3cd 100644
--- a/crates/task-impls/src/helpers.rs
+++ b/crates/task-impls/src/helpers.rs
@@ -50,7 +50,7 @@ use crate::{
 #[instrument(skip_all)]
 #[allow(clippy::too_many_arguments)]
 pub(crate) async fn fetch_proposal<TYPES: NodeType, V: Versions>(
-    view_number: TYPES::Time,
+    view_number: TYPES::View,
     event_sender: Sender<Arc<HotShotEvent<TYPES>>>,
     event_receiver: Receiver<Arc<HotShotEvent<TYPES>>>,
     quorum_membership: Arc<TYPES::Membership>,
@@ -80,6 +80,7 @@ pub(crate) async fn fetch_proposal<TYPES: NodeType, V: Versions>(
     .await;
 
     let mem = Arc::clone(&quorum_membership);
+    let current_epoch = consensus.read().await.cur_epoch();
     // Make a background task to await the arrival of the event data.
     let Ok(Some(proposal)) =
         // We want to explicitly timeout here so we aren't waiting around for the data.
@@ -111,7 +112,7 @@ pub(crate) async fn fetch_proposal<TYPES: NodeType, V: Versions>(
                         hs_event.as_ref()
                     {
                         // Make sure that the quorum_proposal is valid
-                        if quorum_proposal.validate_signature(&mem, upgrade_lock).await.is_ok() {
+                        if quorum_proposal.validate_signature(&mem, current_epoch, upgrade_lock).await.is_ok() {
                             proposal = Some(quorum_proposal.clone());
                         }
 
@@ -130,7 +131,7 @@ pub(crate) async fn fetch_proposal<TYPES: NodeType, V: Versions>(
     let justify_qc = proposal.data.justify_qc.clone();
 
     if !justify_qc
-        .is_valid_cert(quorum_membership.as_ref(), upgrade_lock)
+        .is_valid_cert(quorum_membership.as_ref(), current_epoch, upgrade_lock)
         .await
     {
         bail!("Invalid justify_qc in proposal for view {}", *view_number);
@@ -167,10 +168,10 @@ pub(crate) async fn fetch_proposal<TYPES: NodeType, V: Versions>(
 #[derive(Debug)]
 pub struct LeafChainTraversalOutcome<TYPES: NodeType> {
     /// The new locked view obtained from a 2 chain starting from the proposal's parent.
-    pub new_locked_view_number: Option<TYPES::Time>,
+    pub new_locked_view_number: Option<TYPES::View>,
 
     /// The new decided view obtained from a 3 chain starting from the proposal's parent.
-    pub new_decided_view_number: Option<TYPES::Time>,
+    pub new_decided_view_number: Option<TYPES::View>,
 
     /// The qc for the decided chain.
     pub new_decide_qc: Option<QuorumCertificate<TYPES>>,
@@ -355,7 +356,7 @@ pub async fn decide_from_proposal<TYPES: NodeType>(
 #[instrument(skip_all)]
 #[allow(clippy::too_many_arguments)]
 pub(crate) async fn parent_leaf_and_state<TYPES: NodeType, V: Versions>(
-    next_proposal_view_number: TYPES::Time,
+    next_proposal_view_number: TYPES::View,
     event_sender: &Sender<Arc<HotShotEvent<TYPES>>>,
     event_receiver: &Receiver<Arc<HotShotEvent<TYPES>>>,
     quorum_membership: Arc<TYPES::Membership>,
@@ -364,8 +365,9 @@ pub(crate) async fn parent_leaf_and_state<TYPES: NodeType, V: Versions>(
     consensus: OuterConsensus<TYPES>,
     upgrade_lock: &UpgradeLock<TYPES, V>,
 ) -> Result<(Leaf<TYPES>, Arc<<TYPES as NodeType>::ValidatedState>)> {
+    let current_epoch = consensus.read().await.cur_epoch();
     ensure!(
-        quorum_membership.leader(next_proposal_view_number) == public_key,
+        quorum_membership.leader(next_proposal_view_number, current_epoch) == public_key,
         "Somehow we formed a QC but are not the leader for the next view {next_proposal_view_number:?}",
     );
     let parent_view_number = consensus.read().await.high_qc().view_number();
@@ -485,18 +487,20 @@ pub async fn validate_proposal_safety_and_liveness<
         if let Err(e) = consensus_write.update_proposed_view(proposal.clone()) {
             tracing::debug!("Internal proposal update failed; error = {e:#}");
         };
-
-        // Broadcast that we've updated our consensus state so that other tasks know it's safe to grab.
-        broadcast_event(
-            Arc::new(HotShotEvent::ValidatedStateUpdated(view_number, view)),
-            &event_stream,
-        )
-        .await;
     }
 
+    // Broadcast that we've updated our consensus state so that other tasks know it's safe to grab.
+    broadcast_event(
+        Arc::new(HotShotEvent::ValidatedStateUpdated(view_number, view)),
+        &event_stream,
+    )
+    .await;
+
+    let current_epoch = task_state.cur_epoch;
     UpgradeCertificate::validate(
         &proposal.data.upgrade_certificate,
         &task_state.quorum_membership,
+        current_epoch,
         &task_state.upgrade_lock,
     )
     .await?;
@@ -606,7 +610,11 @@ pub async fn validate_proposal_view_and_certs<
 
     // Validate the proposal's signature. This should also catch if the leaf_commitment does not equal our calculated parent commitment
     proposal
-        .validate_signature(&task_state.quorum_membership, &task_state.upgrade_lock)
+        .validate_signature(
+            &task_state.quorum_membership,
+            task_state.cur_epoch,
+            &task_state.upgrade_lock,
+        )
         .await?;
 
     // Verify a timeout certificate OR a view sync certificate exists and is valid.
@@ -628,6 +636,7 @@ pub async fn validate_proposal_view_and_certs<
                     timeout_cert
                         .is_valid_cert(
                             task_state.timeout_membership.as_ref(),
+                            task_state.cur_epoch,
                             &task_state.upgrade_lock
                         )
                         .await,
@@ -648,6 +657,7 @@ pub async fn validate_proposal_view_and_certs<
                     view_sync_cert
                         .is_valid_cert(
                             task_state.quorum_membership.as_ref(),
+                            task_state.cur_epoch,
                             &task_state.upgrade_lock
                         )
                         .await,
@@ -662,6 +672,7 @@ pub async fn validate_proposal_view_and_certs<
     UpgradeCertificate::validate(
         &proposal.data.upgrade_certificate,
         &task_state.quorum_membership,
+        task_state.cur_epoch,
         &task_state.upgrade_lock,
     )
     .await?;
@@ -675,7 +686,7 @@ pub async fn validate_proposal_view_and_certs<
 /// # Errors
 /// Returns an [`anyhow::Error`] when the new view is not greater than the current view.
 pub(crate) async fn update_view<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>(
-    new_view: TYPES::Time,
+    new_view: TYPES::View,
     event_stream: &Sender<Arc<HotShotEvent<TYPES>>>,
     task_state: &mut QuorumProposalRecvTaskState<TYPES, I, V>,
 ) -> Result<()> {
@@ -684,8 +695,10 @@ pub(crate) async fn update_view<TYPES: NodeType, I: NodeImplementation<TYPES>, V
         "New view is not greater than our current view"
     );
 
-    let is_old_view_leader =
-        task_state.quorum_membership.leader(task_state.cur_view) == task_state.public_key;
+    let is_old_view_leader = task_state
+        .quorum_membership
+        .leader(task_state.cur_view, task_state.cur_epoch)
+        == task_state.public_key;
     let old_view = task_state.cur_view;
 
     debug!("Updating view from {} to {}", *old_view, *new_view);
@@ -722,7 +735,7 @@ pub(crate) async fn update_view<TYPES: NodeType, I: NodeImplementation<TYPES>, V
         async move {
             async_sleep(timeout).await;
             broadcast_event(
-                Arc::new(HotShotEvent::Timeout(TYPES::Time::new(*view_number))),
+                Arc::new(HotShotEvent::Timeout(TYPES::View::new(*view_number))),
                 &stream,
             )
             .await;
diff --git a/crates/task-impls/src/network.rs b/crates/task-impls/src/network.rs
index ca5f6c7aeb..5b897c7b4f 100644
--- a/crates/task-impls/src/network.rs
+++ b/crates/task-impls/src/network.rs
@@ -169,7 +169,7 @@ impl<TYPES: NodeType> NetworkMessageTaskState<TYPES> {
                 // Send the external message to the external event stream so it can be processed
                 broadcast_event(
                     Event {
-                        view_number: TYPES::Time::new(1),
+                        view_number: TYPES::View::new(1),
                         event: EventType::ExternalMessageReceived { sender, data },
                     },
                     &self.external_event_stream,
@@ -190,7 +190,9 @@ pub struct NetworkEventTaskState<
     /// comm network
     pub network: Arc<NET>,
     /// view number
-    pub view: TYPES::Time,
+    pub view: TYPES::View,
+    /// epoch number
+    pub epoch: TYPES::Epoch,
     /// quorum for the network
     pub quorum_membership: TYPES::Membership,
     /// da for the network
@@ -305,7 +307,7 @@ impl<
         maybe_action: Option<HotShotAction>,
         storage: Arc<RwLock<S>>,
         state: Arc<RwLock<Consensus<TYPES>>>,
-        view: <TYPES as NodeType>::Time,
+        view: <TYPES as NodeType>::View,
     ) -> Result<(), ()> {
         if let Some(action) = maybe_action {
             if !state.write().await.update_action(action, view) {
@@ -358,7 +360,10 @@ impl<
                     MessageKind::<TYPES>::from_consensus_message(SequencingMessage::General(
                         GeneralConsensusMessage::Vote(vote.clone()),
                     )),
-                    TransmitType::Direct(self.quorum_membership.leader(vote.view_number() + 1)),
+                    TransmitType::Direct(
+                        self.quorum_membership
+                            .leader(vote.view_number() + 1, self.epoch),
+                    ),
                 ))
             }
             HotShotEvent::QuorumProposalRequestSend(req, signature) => Some((
@@ -396,7 +401,10 @@ impl<
                     MessageKind::<TYPES>::from_consensus_message(SequencingMessage::Da(
                         DaConsensusMessage::DaVote(vote.clone()),
                     )),
-                    TransmitType::Direct(self.quorum_membership.leader(vote.view_number())),
+                    TransmitType::Direct(
+                        self.quorum_membership
+                            .leader(vote.view_number(), self.epoch),
+                    ),
                 ))
             }
             HotShotEvent::DacSend(certificate, sender) => {
@@ -416,7 +424,7 @@ impl<
                 )),
                 TransmitType::Direct(
                     self.quorum_membership
-                        .leader(vote.view_number() + vote.date().relay),
+                        .leader(vote.view_number() + vote.date().relay, self.epoch),
                 ),
             )),
             HotShotEvent::ViewSyncCommitVoteSend(vote) => Some((
@@ -426,7 +434,7 @@ impl<
                 )),
                 TransmitType::Direct(
                     self.quorum_membership
-                        .leader(vote.view_number() + vote.date().relay),
+                        .leader(vote.view_number() + vote.date().relay, self.epoch),
                 ),
             )),
             HotShotEvent::ViewSyncFinalizeVoteSend(vote) => Some((
@@ -436,7 +444,7 @@ impl<
                 )),
                 TransmitType::Direct(
                     self.quorum_membership
-                        .leader(vote.view_number() + vote.date().relay),
+                        .leader(vote.view_number() + vote.date().relay, self.epoch),
                 ),
             )),
             HotShotEvent::ViewSyncPreCommitCertificate2Send(certificate, sender) => Some((
@@ -467,7 +475,10 @@ impl<
                     MessageKind::<TYPES>::from_consensus_message(SequencingMessage::General(
                         GeneralConsensusMessage::TimeoutVote(vote.clone()),
                     )),
-                    TransmitType::Direct(self.quorum_membership.leader(vote.view_number() + 1)),
+                    TransmitType::Direct(
+                        self.quorum_membership
+                            .leader(vote.view_number() + 1, self.epoch),
+                    ),
                 ))
             }
             HotShotEvent::UpgradeProposalSend(proposal, sender) => Some((
@@ -484,13 +495,20 @@ impl<
                     MessageKind::<TYPES>::from_consensus_message(SequencingMessage::General(
                         GeneralConsensusMessage::UpgradeVote(vote.clone()),
                     )),
-                    TransmitType::Direct(self.quorum_membership.leader(vote.view_number())),
+                    TransmitType::Direct(
+                        self.quorum_membership
+                            .leader(vote.view_number(), self.epoch),
+                    ),
                 ))
             }
             HotShotEvent::ViewChange(view) => {
                 self.view = view;
                 self.network
-                    .update_view::<TYPES>(self.view.u64(), &self.quorum_membership)
+                    .update_view::<TYPES>(
+                        self.view.u64(),
+                        self.epoch.u64(),
+                        &self.quorum_membership,
+                    )
                     .await;
                 None
             }
@@ -534,7 +552,7 @@ impl<
         };
         let view = message.kind.view_number();
         let committee_topic = self.quorum_membership.committee_topic();
-        let da_committee = self.da_membership.committee_members(view);
+        let da_committee = self.da_membership.committee_members(view, self.epoch);
         let net = Arc::clone(&self.network);
         let storage = Arc::clone(&self.storage);
         let state = Arc::clone(&self.consensus);
diff --git a/crates/task-impls/src/quorum_proposal/handlers.rs b/crates/task-impls/src/quorum_proposal/handlers.rs
index e53a618320..bcdc568e18 100644
--- a/crates/task-impls/src/quorum_proposal/handlers.rs
+++ b/crates/task-impls/src/quorum_proposal/handlers.rs
@@ -60,10 +60,10 @@ pub(crate) enum ProposalDependency {
 /// Handler for the proposal dependency
 pub struct ProposalDependencyHandle<TYPES: NodeType, V: Versions> {
     /// Latest view number that has been proposed for (proxy for cur_view).
-    pub latest_proposed_view: TYPES::Time,
+    pub latest_proposed_view: TYPES::View,
 
     /// The view number to propose for.
-    pub view_number: TYPES::Time,
+    pub view_number: TYPES::View,
 
     /// The event sender.
     pub sender: Sender<Arc<HotShotEvent<TYPES>>>,
diff --git a/crates/task-impls/src/quorum_proposal/mod.rs b/crates/task-impls/src/quorum_proposal/mod.rs
index 2c12b83b28..7390427f09 100644
--- a/crates/task-impls/src/quorum_proposal/mod.rs
+++ b/crates/task-impls/src/quorum_proposal/mod.rs
@@ -46,10 +46,10 @@ mod handlers;
 /// The state for the quorum proposal task.
 pub struct QuorumProposalTaskState<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> {
     /// Latest view number that has been proposed for.
-    pub latest_proposed_view: TYPES::Time,
+    pub latest_proposed_view: TYPES::View,
 
     /// Table for the in-progress proposal dependency tasks.
-    pub proposal_dependencies: HashMap<TYPES::Time, JoinHandle<()>>,
+    pub proposal_dependencies: HashMap<TYPES::View, JoinHandle<()>>,
 
     /// The underlying network
     pub network: Arc<I::Network>,
@@ -107,7 +107,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>
     fn create_event_dependency(
         &self,
         dependency_type: ProposalDependency,
-        view_number: TYPES::Time,
+        view_number: TYPES::View,
         event_receiver: Receiver<Arc<HotShotEvent<TYPES>>>,
     ) -> EventDependency<Arc<HotShotEvent<TYPES>>> {
         EventDependency::new(
@@ -181,7 +181,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>
     /// Creates the requisite dependencies for the Quorum Proposal task. It also handles any event forwarding.
     fn create_and_complete_dependencies(
         &self,
-        view_number: TYPES::Time,
+        view_number: TYPES::View,
         event_receiver: &Receiver<Arc<HotShotEvent<TYPES>>>,
         event: Arc<HotShotEvent<TYPES>>,
     ) -> AndDependency<Vec<Vec<Arc<HotShotEvent<TYPES>>>>> {
@@ -283,13 +283,14 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>
     #[instrument(skip_all, fields(id = self.id, latest_proposed_view = *self.latest_proposed_view), name = "Create dependency task", level = "error")]
     fn create_dependency_task_if_new(
         &mut self,
-        view_number: TYPES::Time,
+        view_number: TYPES::View,
+        epoch_number: TYPES::Epoch,
         event_receiver: Receiver<Arc<HotShotEvent<TYPES>>>,
         event_sender: Sender<Arc<HotShotEvent<TYPES>>>,
         event: Arc<HotShotEvent<TYPES>>,
     ) {
         // Don't even bother making the task if we are not entitled to propose anyway.
-        if self.quorum_membership.leader(view_number) != self.public_key {
+        if self.quorum_membership.leader(view_number, epoch_number) != self.public_key {
             tracing::trace!("We are not the leader of the next view");
             return;
         }
@@ -333,7 +334,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>
 
     /// Update the latest proposed view number.
     #[instrument(skip_all, fields(id = self.id, latest_proposed_view = *self.latest_proposed_view), name = "Update latest proposed view", level = "error")]
-    async fn update_latest_proposed_view(&mut self, new_view: TYPES::Time) -> bool {
+    async fn update_latest_proposed_view(&mut self, new_view: TYPES::View) -> bool {
         if *self.latest_proposed_view < *new_view {
             debug!(
                 "Updating latest proposed view from {} to {}",
@@ -342,7 +343,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>
 
             // Cancel the old dependency tasks.
             for view in (*self.latest_proposed_view + 1)..=(*new_view) {
-                if let Some(dependency) = self.proposal_dependencies.remove(&TYPES::Time::new(view))
+                if let Some(dependency) = self.proposal_dependencies.remove(&TYPES::View::new(view))
                 {
                     cancel_task(dependency).await;
                 }
@@ -380,9 +381,11 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>
             HotShotEvent::QcFormed(cert) => match cert.clone() {
                 either::Right(timeout_cert) => {
                     let view_number = timeout_cert.view_number + 1;
+                    let epoch_number = self.consensus.read().await.cur_epoch();
 
                     self.create_dependency_task_if_new(
                         view_number,
+                        epoch_number,
                         event_receiver,
                         event_sender,
                         Arc::clone(&event),
@@ -411,17 +414,24 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>
                 _auction_result,
             ) => {
                 let view_number = *view_number;
+                let epoch_number = self.consensus.read().await.cur_epoch();
 
                 self.create_dependency_task_if_new(
                     view_number,
+                    epoch_number,
                     event_receiver,
                     event_sender,
                     Arc::clone(&event),
                 );
             }
             HotShotEvent::ViewSyncFinalizeCertificate2Recv(certificate) => {
+                let epoch_number = self.consensus.read().await.cur_epoch();
                 if !certificate
-                    .is_valid_cert(self.quorum_membership.as_ref(), &self.upgrade_lock)
+                    .is_valid_cert(
+                        self.quorum_membership.as_ref(),
+                        epoch_number,
+                        &self.upgrade_lock,
+                    )
                     .await
                 {
                     warn!(
@@ -435,6 +445,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>
 
                 self.create_dependency_task_if_new(
                     view_number,
+                    epoch_number,
                     event_receiver,
                     event_sender,
                     event,
@@ -447,9 +458,11 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>
                 if !self.update_latest_proposed_view(view_number).await {
                     tracing::trace!("Failed to update latest proposed view");
                 }
+                let epoch_number = self.consensus.read().await.cur_epoch();
 
                 self.create_dependency_task_if_new(
                     view_number + 1,
+                    epoch_number,
                     event_receiver,
                     event_sender,
                     Arc::clone(&event),
@@ -464,9 +477,11 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>
             }
             HotShotEvent::VidDisperseSend(vid_share, _) => {
                 let view_number = vid_share.data.view_number();
+                let epoch_number = self.consensus.read().await.cur_epoch();
 
                 self.create_dependency_task_if_new(
                     view_number,
+                    epoch_number,
                     event_receiver,
                     event_sender,
                     Arc::clone(&event),
@@ -490,8 +505,10 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>
             }
             HotShotEvent::HighQcUpdated(qc) => {
                 let view_number = qc.view_number() + 1;
+                let epoch_number = self.consensus.read().await.cur_epoch();
                 self.create_dependency_task_if_new(
                     view_number,
+                    epoch_number,
                     event_receiver,
                     event_sender,
                     Arc::clone(&event),
diff --git a/crates/task-impls/src/quorum_proposal_recv/handlers.rs b/crates/task-impls/src/quorum_proposal_recv/handlers.rs
index c268c14b0e..2193bf3dfd 100644
--- a/crates/task-impls/src/quorum_proposal_recv/handlers.rs
+++ b/crates/task-impls/src/quorum_proposal_recv/handlers.rs
@@ -136,6 +136,7 @@ pub(crate) async fn handle_quorum_proposal_recv<
     if !justify_qc
         .is_valid_cert(
             task_state.quorum_membership.as_ref(),
+            task_state.cur_epoch,
             &task_state.upgrade_lock,
         )
         .await
diff --git a/crates/task-impls/src/quorum_proposal_recv/mod.rs b/crates/task-impls/src/quorum_proposal_recv/mod.rs
index f51a8d5e00..281e472fd0 100644
--- a/crates/task-impls/src/quorum_proposal_recv/mod.rs
+++ b/crates/task-impls/src/quorum_proposal_recv/mod.rs
@@ -55,11 +55,14 @@ pub struct QuorumProposalRecvTaskState<TYPES: NodeType, I: NodeImplementation<TY
     pub consensus: OuterConsensus<TYPES>,
 
     /// View number this view is executing in.
-    pub cur_view: TYPES::Time,
+    pub cur_view: TYPES::View,
 
     /// Timestamp this view starts at.
     pub cur_view_time: i64,
 
+    /// Epoch number this node is executing in.
+    pub cur_epoch: TYPES::Epoch,
+
     /// The underlying network
     pub network: Arc<I::Network>,
 
@@ -89,7 +92,7 @@ pub struct QuorumProposalRecvTaskState<TYPES: NodeType, I: NodeImplementation<TY
 
     /// Spawned tasks related to a specific view, so we can cancel them when
     /// they are stale
-    pub spawned_tasks: BTreeMap<TYPES::Time, Vec<JoinHandle<()>>>,
+    pub spawned_tasks: BTreeMap<TYPES::View, Vec<JoinHandle<()>>>,
 
     /// Immutable instance state
     pub instance_state: Arc<TYPES::InstanceState>,
@@ -105,7 +108,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>
     QuorumProposalRecvTaskState<TYPES, I, V>
 {
     /// Cancel all tasks the consensus tasks has spawned before the given view
-    pub async fn cancel_tasks(&mut self, view: TYPES::Time) {
+    pub async fn cancel_tasks(&mut self, view: TYPES::View) {
         let keep = self.spawned_tasks.split_off(&view);
         let mut cancel = Vec::new();
         while let Some((_, tasks)) = self.spawned_tasks.pop_first() {
diff --git a/crates/task-impls/src/quorum_vote/mod.rs b/crates/task-impls/src/quorum_vote/mod.rs
index ed0d61d4e9..909fcf2db2 100644
--- a/crates/task-impls/src/quorum_vote/mod.rs
+++ b/crates/task-impls/src/quorum_vote/mod.rs
@@ -75,7 +75,9 @@ pub struct VoteDependencyHandle<TYPES: NodeType, I: NodeImplementation<TYPES>, V
     /// Reference to the storage.
     pub storage: Arc<RwLock<I::Storage>>,
     /// View number to vote on.
-    pub view_number: TYPES::Time,
+    pub view_number: TYPES::View,
+    /// Epoch number to vote on.
+    pub epoch_number: TYPES::Epoch,
     /// Event sender.
     pub sender: Sender<Arc<HotShotEvent<TYPES>>>,
     /// Event receiver.
@@ -200,7 +202,8 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES> + 'static, V: Versions>
         vid_share: Proposal<TYPES, VidDisperseShare<TYPES>>,
     ) -> Result<()> {
         ensure!(
-            self.quorum_membership.has_stake(&self.public_key),
+            self.quorum_membership
+                .has_stake(&self.public_key, self.epoch_number),
             format!(
                 "We were not chosen for quorum committee on {:?}",
                 self.view_number
@@ -373,10 +376,10 @@ pub struct QuorumVoteTaskState<TYPES: NodeType, I: NodeImplementation<TYPES>, V:
     pub instance_state: Arc<TYPES::InstanceState>,
 
     /// Latest view number that has been voted for.
-    pub latest_voted_view: TYPES::Time,
+    pub latest_voted_view: TYPES::View,
 
     /// Table for the in-progress dependency tasks.
-    pub vote_dependencies: HashMap<TYPES::Time, JoinHandle<()>>,
+    pub vote_dependencies: HashMap<TYPES::View, JoinHandle<()>>,
 
     /// The underlying network
     pub network: Arc<I::Network>,
@@ -406,7 +409,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> QuorumVoteTaskS
     fn create_event_dependency(
         &self,
         dependency_type: VoteDependency,
-        view_number: TYPES::Time,
+        view_number: TYPES::View,
         event_receiver: Receiver<Arc<HotShotEvent<TYPES>>>,
     ) -> EventDependency<Arc<HotShotEvent<TYPES>>> {
         EventDependency::new(
@@ -450,7 +453,8 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> QuorumVoteTaskS
     #[instrument(skip_all, fields(id = self.id, latest_voted_view = *self.latest_voted_view), name = "Quorum vote crete dependency task if new", level = "error")]
     fn create_dependency_task_if_new(
         &mut self,
-        view_number: TYPES::Time,
+        view_number: TYPES::View,
+        epoch_number: TYPES::Epoch,
         event_receiver: Receiver<Arc<HotShotEvent<TYPES>>>,
         event_sender: &Sender<Arc<HotShotEvent<TYPES>>>,
         event: Option<Arc<HotShotEvent<TYPES>>>,
@@ -493,6 +497,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> QuorumVoteTaskS
                 quorum_membership: Arc::clone(&self.quorum_membership),
                 storage: Arc::clone(&self.storage),
                 view_number,
+                epoch_number,
                 sender: event_sender.clone(),
                 receiver: event_receiver.clone(),
                 upgrade_lock: self.upgrade_lock.clone(),
@@ -505,7 +510,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> QuorumVoteTaskS
 
     /// Update the latest voted view number.
     #[instrument(skip_all, fields(id = self.id, latest_voted_view = *self.latest_voted_view), name = "Quorum vote update latest voted view", level = "error")]
-    async fn update_latest_voted_view(&mut self, new_view: TYPES::Time) -> bool {
+    async fn update_latest_voted_view(&mut self, new_view: TYPES::View) -> bool {
         if *self.latest_voted_view < *new_view {
             debug!(
                 "Updating next vote view from {} to {} in the quorum vote task",
@@ -514,7 +519,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> QuorumVoteTaskS
 
             // Cancel the old dependency tasks.
             for view in *self.latest_voted_view..(*new_view) {
-                if let Some(dependency) = self.vote_dependencies.remove(&TYPES::Time::new(view)) {
+                if let Some(dependency) = self.vote_dependencies.remove(&TYPES::View::new(view)) {
                     cancel_task(dependency).await;
                     debug!("Vote dependency removed for view {:?}", view);
                 }
@@ -535,6 +540,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> QuorumVoteTaskS
         event_receiver: Receiver<Arc<HotShotEvent<TYPES>>>,
         event_sender: Sender<Arc<HotShotEvent<TYPES>>>,
     ) {
+        let current_epoch = self.consensus.read().await.cur_epoch();
         match event.as_ref() {
             HotShotEvent::QuorumProposalValidated(proposal, _leaf) => {
                 trace!("Received Proposal for view {}", *proposal.view_number());
@@ -548,6 +554,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> QuorumVoteTaskS
 
                 self.create_dependency_task_if_new(
                     proposal.view_number,
+                    current_epoch,
                     event_receiver,
                     &event_sender,
                     Some(Arc::clone(&event)),
@@ -560,9 +567,14 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> QuorumVoteTaskS
                     return;
                 }
 
+                let current_epoch = self.consensus.read().await.cur_epoch();
                 // Validate the DAC.
                 if !cert
-                    .is_valid_cert(self.da_membership.as_ref(), &self.upgrade_lock)
+                    .is_valid_cert(
+                        self.da_membership.as_ref(),
+                        current_epoch,
+                        &self.upgrade_lock,
+                    )
                     .await
                 {
                     return;
@@ -579,7 +591,13 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> QuorumVoteTaskS
                     &event_sender.clone(),
                 )
                 .await;
-                self.create_dependency_task_if_new(view, event_receiver, &event_sender, None);
+                self.create_dependency_task_if_new(
+                    view,
+                    current_epoch,
+                    event_receiver,
+                    &event_sender,
+                    None,
+                );
             }
             HotShotEvent::VidShareRecv(sender, disperse) => {
                 let view = disperse.data.view_number();
@@ -590,10 +608,14 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> QuorumVoteTaskS
 
                 // Validate the VID share.
                 let payload_commitment = disperse.data.payload_commitment;
+                let current_epoch = self.consensus.read().await.cur_epoch();
                 // Check sender of VID disperse share is signed by DA committee member
                 let validate_sender = sender
                     .validate(&disperse.signature, payload_commitment.as_ref())
-                    && self.da_membership.committee_members(view).contains(sender);
+                    && self
+                        .da_membership
+                        .committee_members(view, current_epoch)
+                        .contains(sender);
 
                 // Check whether the data satisfies one of the following.
                 // * From the right leader for this view.
@@ -603,7 +625,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> QuorumVoteTaskS
                     .validate(&disperse.signature, payload_commitment.as_ref())
                     || self
                         .quorum_membership
-                        .leader(view)
+                        .leader(view, current_epoch)
                         .validate(&disperse.signature, payload_commitment.as_ref());
                 if !validate_sender && !validated {
                     warn!("Failed to validated the VID dispersal/share sig.");
@@ -613,7 +635,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> QuorumVoteTaskS
                 // NOTE: `verify_share` returns a nested `Result`, so we must check both the inner
                 // and outer results
                 #[allow(clippy::no_effect)]
-                match vid_scheme(self.quorum_membership.total_nodes()).verify_share(
+                match vid_scheme(self.quorum_membership.total_nodes(current_epoch)).verify_share(
                     &disperse.data.share,
                     &disperse.data.common,
                     &payload_commitment,
@@ -641,7 +663,13 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> QuorumVoteTaskS
                     &event_sender.clone(),
                 )
                 .await;
-                self.create_dependency_task_if_new(view, event_receiver, &event_sender, None);
+                self.create_dependency_task_if_new(
+                    view,
+                    current_epoch,
+                    event_receiver,
+                    &event_sender,
+                    None,
+                );
             }
             HotShotEvent::QuorumVoteDependenciesValidated(view_number) => {
                 debug!("All vote dependencies verified for view {:?}", view_number);
diff --git a/crates/task-impls/src/request.rs b/crates/task-impls/src/request.rs
index 4ea5966fec..8cd336e7b1 100644
--- a/crates/task-impls/src/request.rs
+++ b/crates/task-impls/src/request.rs
@@ -56,7 +56,7 @@ pub struct NetworkRequestState<TYPES: NodeType, I: NodeImplementation<TYPES>> {
     /// before sending a request
     pub state: OuterConsensus<TYPES>,
     /// Last seen view, we won't request for proposals before older than this view
-    pub view: TYPES::Time,
+    pub view: TYPES::View,
     /// Delay before requesting peers
     pub delay: Duration,
     /// DA Membership
@@ -70,7 +70,7 @@ pub struct NetworkRequestState<TYPES: NodeType, I: NodeImplementation<TYPES>> {
     /// A flag indicating that `HotShotEvent::Shutdown` has been received
     pub shutdown_flag: Arc<AtomicBool>,
     /// A flag indicating that `HotShotEvent::Shutdown` has been received
-    pub spawned_tasks: BTreeMap<TYPES::Time, Vec<JoinHandle<()>>>,
+    pub spawned_tasks: BTreeMap<TYPES::View, Vec<JoinHandle<()>>>,
 }
 
 impl<TYPES: NodeType, I: NodeImplementation<TYPES>> Drop for NetworkRequestState<TYPES, I> {
@@ -97,6 +97,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>> TaskState for NetworkRequest
         match event.as_ref() {
             HotShotEvent::QuorumProposalValidated(proposal, _) => {
                 let prop_view = proposal.view_number();
+                let current_epoch = self.state.read().await.cur_epoch();
 
                 // If we already have the VID shares for the next view, do nothing.
                 if prop_view >= self.view
@@ -107,7 +108,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>> TaskState for NetworkRequest
                         .vid_shares()
                         .contains_key(&prop_view)
                 {
-                    self.spawn_requests(prop_view, sender, receiver);
+                    self.spawn_requests(prop_view, current_epoch, sender, receiver);
                 }
                 Ok(())
             }
@@ -144,7 +145,8 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>> NetworkRequestState<TYPES, I
     /// Creates and signs the payload, then will create a request task
     fn spawn_requests(
         &mut self,
-        view: TYPES::Time,
+        view: TYPES::View,
+        epoch: TYPES::Epoch,
         sender: &Sender<Arc<HotShotEvent<TYPES>>>,
         receiver: &Receiver<Arc<HotShotEvent<TYPES>>>,
     ) {
@@ -158,6 +160,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>> NetworkRequestState<TYPES, I
                 sender.clone(),
                 receiver.clone(),
                 view,
+                epoch,
             );
         }
     }
@@ -170,19 +173,20 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>> NetworkRequestState<TYPES, I
         signature: Signature<TYPES>,
         sender: Sender<Arc<HotShotEvent<TYPES>>>,
         receiver: Receiver<Arc<HotShotEvent<TYPES>>>,
-        view: TYPES::Time,
+        view: TYPES::View,
+        epoch: TYPES::Epoch,
     ) {
         let state = OuterConsensus::new(Arc::clone(&self.state.inner_consensus));
         let network = Arc::clone(&self.network);
         let shutdown_flag = Arc::clone(&self.shutdown_flag);
         let delay = self.delay;
-        let da_committee_for_view = self.da_membership.committee_members(view);
+        let da_committee_for_view = self.da_membership.committee_members(view, epoch);
         let public_key = self.public_key.clone();
 
         // Get committee members for view
         let mut recipients: Vec<TYPES::SignatureKey> = self
             .da_membership
-            .committee_members(view)
+            .committee_members(view, epoch)
             .into_iter()
             .collect();
         // Randomize the recipients so all replicas don't overload the same 1 recipients
@@ -256,7 +260,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>> NetworkRequestState<TYPES, I
         recipient: &TYPES::SignatureKey,
         da_committee_for_view: &BTreeSet<<TYPES as NodeType>::SignatureKey>,
         public_key: &<TYPES as NodeType>::SignatureKey,
-        view: TYPES::Time,
+        view: TYPES::View,
     ) -> bool {
         // First send request to a random DA member for the view
         broadcast_event(
@@ -299,7 +303,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>> NetworkRequestState<TYPES, I
     async fn handle_event_dependency(
         receiver: &Receiver<Arc<HotShotEvent<TYPES>>>,
         da_members_for_view: BTreeSet<<TYPES as NodeType>::SignatureKey>,
-        view: TYPES::Time,
+        view: TYPES::View,
     ) -> Option<Arc<HotShotEvent<TYPES>>> {
         EventDependency::new(
             receiver.clone(),
@@ -326,7 +330,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>> NetworkRequestState<TYPES, I
         state: &OuterConsensus<TYPES>,
         sender: &Sender<Arc<HotShotEvent<TYPES>>>,
         public_key: &<TYPES as NodeType>::SignatureKey,
-        view: &TYPES::Time,
+        view: &TYPES::View,
         shutdown_flag: &Arc<AtomicBool>,
     ) -> bool {
         let state = state.read().await;
diff --git a/crates/task-impls/src/response.rs b/crates/task-impls/src/response.rs
index e8e8483b08..475a843896 100644
--- a/crates/task-impls/src/response.rs
+++ b/crates/task-impls/src/response.rs
@@ -76,7 +76,7 @@ impl<TYPES: NodeType> NetworkResponseState<TYPES> {
                     match event.as_ref() {
                         HotShotEvent::VidRequestRecv(request, sender) => {
                             // Verify request is valid
-                            if !self.valid_sender(sender)
+                            if !self.valid_sender(sender, self.consensus.read().await.cur_epoch())
                                 || !valid_signature::<TYPES>(request, sender)
                             {
                                 continue;
@@ -140,7 +140,7 @@ impl<TYPES: NodeType> NetworkResponseState<TYPES> {
     #[instrument(skip_all, target = "NetworkResponseState", fields(id = self.id))]
     async fn get_or_calc_vid_share(
         &self,
-        view: TYPES::Time,
+        view: TYPES::View,
         key: &TYPES::SignatureKey,
     ) -> Option<Proposal<TYPES, VidDisperseShare<TYPES>>> {
         let contained = self
@@ -151,11 +151,13 @@ impl<TYPES: NodeType> NetworkResponseState<TYPES> {
             .get(&view)
             .is_some_and(|m| m.contains_key(key));
         if !contained {
+            let current_epoch = self.consensus.read().await.cur_epoch();
             if Consensus::calculate_and_update_vid(
                 OuterConsensus::new(Arc::clone(&self.consensus)),
                 view,
                 Arc::clone(&self.quorum),
                 &self.private_key,
+                current_epoch,
             )
             .await
             .is_none()
@@ -167,6 +169,7 @@ impl<TYPES: NodeType> NetworkResponseState<TYPES> {
                     view,
                     Arc::clone(&self.quorum),
                     &self.private_key,
+                    current_epoch,
                 )
                 .await?;
             }
@@ -188,9 +191,9 @@ impl<TYPES: NodeType> NetworkResponseState<TYPES> {
             .cloned()
     }
 
-    /// Makes sure the sender is allowed to send a request.
-    fn valid_sender(&self, sender: &TYPES::SignatureKey) -> bool {
-        self.quorum.has_stake(sender)
+    /// Makes sure the sender is allowed to send a request in the given epoch.
+    fn valid_sender(&self, sender: &TYPES::SignatureKey, epoch: TYPES::Epoch) -> bool {
+        self.quorum.has_stake(sender, epoch)
     }
 }
 
diff --git a/crates/task-impls/src/transactions.rs b/crates/task-impls/src/transactions.rs
index bd1aa73307..354d9d1fd6 100644
--- a/crates/task-impls/src/transactions.rs
+++ b/crates/task-impls/src/transactions.rs
@@ -82,7 +82,10 @@ pub struct TransactionTaskState<TYPES: NodeType, I: NodeImplementation<TYPES>, V
     pub output_event_stream: async_broadcast::Sender<Event<TYPES>>,
 
     /// View number this view is executing in.
-    pub cur_view: TYPES::Time,
+    pub cur_view: TYPES::View,
+
+    /// Epoch number this node is executing in.
+    pub cur_epoch: TYPES::Epoch,
 
     /// Reference to consensus. Leader will require a read lock on this.
     pub consensus: OuterConsensus<TYPES>,
@@ -117,7 +120,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> TransactionTask
     pub async fn handle_view_change(
         &mut self,
         event_stream: &Sender<Arc<HotShotEvent<TYPES>>>,
-        block_view: TYPES::Time,
+        block_view: TYPES::View,
     ) -> Option<HotShotTaskCompleted> {
         let version = match self.upgrade_lock.version(block_view).await {
             Ok(v) => v,
@@ -141,7 +144,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> TransactionTask
     pub async fn handle_view_change_legacy(
         &mut self,
         event_stream: &Sender<Arc<HotShotEvent<TYPES>>>,
-        block_view: TYPES::Time,
+        block_view: TYPES::View,
     ) -> Option<HotShotTaskCompleted> {
         let version = match self.upgrade_lock.version(block_view).await {
             Ok(v) => v,
@@ -201,10 +204,11 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> TransactionTask
                 .number_of_empty_blocks_proposed
                 .add(1);
 
-            let membership_total_nodes = self.membership.total_nodes();
-            let Some(null_fee) =
-                null_block::builder_fee::<TYPES, V>(self.membership.total_nodes(), version)
-            else {
+            let membership_total_nodes = self.membership.total_nodes(self.cur_epoch);
+            let Some(null_fee) = null_block::builder_fee::<TYPES, V>(
+                self.membership.total_nodes(self.cur_epoch),
+                version,
+            ) else {
                 error!("Failed to get null fee");
                 return None;
             };
@@ -239,7 +243,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> TransactionTask
     /// Returns an error if the solver cannot be contacted, or if none of the builders respond.
     async fn produce_block_marketplace(
         &mut self,
-        block_view: TYPES::Time,
+        block_view: TYPES::View,
         task_start_time: Instant,
     ) -> Result<PackedBundle<TYPES>> {
         ensure!(
@@ -336,13 +340,14 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> TransactionTask
     /// Produce a null block
     pub fn null_block(
         &self,
-        block_view: TYPES::Time,
+        block_view: TYPES::View,
         version: Version,
     ) -> Option<PackedBundle<TYPES>> {
-        let membership_total_nodes = self.membership.total_nodes();
-        let Some(null_fee) =
-            null_block::builder_fee::<TYPES, V>(self.membership.total_nodes(), version)
-        else {
+        let membership_total_nodes = self.membership.total_nodes(self.cur_epoch);
+        let Some(null_fee) = null_block::builder_fee::<TYPES, V>(
+            self.membership.total_nodes(self.cur_epoch),
+            version,
+        ) else {
             error!("Failed to calculate null block fee.");
             return None;
         };
@@ -367,7 +372,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> TransactionTask
     pub async fn handle_view_change_marketplace(
         &mut self,
         event_stream: &Sender<Arc<HotShotEvent<TYPES>>>,
-        block_view: TYPES::Time,
+        block_view: TYPES::View,
     ) -> Option<HotShotTaskCompleted> {
         let task_start_time = Instant::now();
 
@@ -446,12 +451,13 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> TransactionTask
                 let mut make_block = false;
                 if *view - *self.cur_view > 1 {
                     info!("View changed by more than 1 going to view {:?}", view);
-                    make_block = self.membership.leader(view) == self.public_key;
+                    make_block = self.membership.leader(view, self.cur_epoch) == self.public_key;
                 }
                 self.cur_view = view;
 
                 let next_view = self.cur_view + 1;
-                let next_leader = self.membership.leader(next_view) == self.public_key;
+                let next_leader =
+                    self.membership.leader(next_view, self.cur_epoch) == self.public_key;
                 if !make_block && !next_leader {
                     debug!("Not next leader for view {:?}", self.cur_view);
                     return None;
@@ -478,9 +484,9 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> TransactionTask
     #[instrument(skip_all, target = "TransactionTaskState", fields(id = self.id, cur_view = *self.cur_view, block_view = *block_view))]
     async fn last_vid_commitment_retry(
         &self,
-        block_view: TYPES::Time,
+        block_view: TYPES::View,
         task_start_time: Instant,
-    ) -> Result<(TYPES::Time, VidCommitment)> {
+    ) -> Result<(TYPES::View, VidCommitment)> {
         loop {
             match self.last_vid_commitment(block_view).await {
                 Ok((view, comm)) => break Ok((view, comm)),
@@ -499,10 +505,10 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> TransactionTask
     #[instrument(skip_all, target = "TransactionTaskState", fields(id = self.id, cur_view = *self.cur_view, block_view = *block_view))]
     async fn last_vid_commitment(
         &self,
-        block_view: TYPES::Time,
-    ) -> Result<(TYPES::Time, VidCommitment)> {
+        block_view: TYPES::View,
+    ) -> Result<(TYPES::View, VidCommitment)> {
         let consensus = self.consensus.read().await;
-        let mut target_view = TYPES::Time::new(block_view.saturating_sub(1));
+        let mut target_view = TYPES::View::new(block_view.saturating_sub(1));
 
         loop {
             let view_data = consensus
@@ -525,7 +531,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> TransactionTask
                 ViewInner::Failed => {
                     // For failed views, backtrack
                     target_view =
-                        TYPES::Time::new(target_view.checked_sub(1).context("Reached genesis")?);
+                        TYPES::View::new(target_view.checked_sub(1).context("Reached genesis")?);
                     continue;
                 }
             }
@@ -533,7 +539,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> TransactionTask
     }
 
     #[instrument(skip_all, fields(id = self.id, cur_view = *self.cur_view, block_view = *block_view), name = "wait_for_block", level = "error")]
-    async fn wait_for_block(&self, block_view: TYPES::Time) -> Option<BuilderResponse<TYPES>> {
+    async fn wait_for_block(&self, block_view: TYPES::View) -> Option<BuilderResponse<TYPES>> {
         let task_start_time = Instant::now();
 
         // Find commitment to the block we want to build upon
@@ -597,7 +603,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> TransactionTask
     async fn get_available_blocks(
         &self,
         parent_comm: VidCommitment,
-        view_number: TYPES::Time,
+        view_number: TYPES::View,
         parent_comm_sig: &<<TYPES as NodeType>::SignatureKey as SignatureKey>::PureAssembledSignatureType,
     ) -> Vec<(AvailableBlockInfo<TYPES>, usize)> {
         let tasks = self
@@ -666,7 +672,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> TransactionTask
     async fn block_from_builder(
         &self,
         parent_comm: VidCommitment,
-        view_number: TYPES::Time,
+        view_number: TYPES::View,
         parent_comm_sig: &<<TYPES as NodeType>::SignatureKey as SignatureKey>::PureAssembledSignatureType,
     ) -> anyhow::Result<BuilderResponse<TYPES>> {
         let mut available_blocks = self
diff --git a/crates/task-impls/src/upgrade.rs b/crates/task-impls/src/upgrade.rs
index d050ef4e54..4992b06887 100644
--- a/crates/task-impls/src/upgrade.rs
+++ b/crates/task-impls/src/upgrade.rs
@@ -43,7 +43,10 @@ pub struct UpgradeTaskState<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Ve
     pub output_event_stream: async_broadcast::Sender<Event<TYPES>>,
 
     /// View number this view is executing in.
-    pub cur_view: TYPES::Time,
+    pub cur_view: TYPES::View,
+
+    /// Epoch number this node is executing in.
+    pub cur_epoch: TYPES::Epoch,
 
     /// Membership for Quorum Certs/votes
     pub quorum_membership: Arc<TYPES::Membership>,
@@ -166,7 +169,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> UpgradeTaskStat
                 // the `UpgradeProposalRecv` event. Otherwise, the view number subtraction below will
                 // cause an overflow error.
                 // TODO Come back to this - we probably don't need this, but we should also never receive a UpgradeCertificate where this fails, investigate block ready so it doesn't make one for the genesis block
-                if self.cur_view != TYPES::Time::genesis() && view < self.cur_view - 1 {
+                if self.cur_view != TYPES::View::genesis() && view < self.cur_view - 1 {
                     warn!("Discarding old upgrade proposal; the proposal is for view {:?}, but the current view is {:?}.",
                       view,
                       self.cur_view
@@ -175,7 +178,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> UpgradeTaskStat
                 }
 
                 // We then validate that the proposal was issued by the leader for the view.
-                let view_leader_key = self.quorum_membership.leader(view);
+                let view_leader_key = self.quorum_membership.leader(view, self.cur_epoch);
                 if &view_leader_key != sender {
                     error!("Upgrade proposal doesn't have expected leader key for view {} \n Upgrade proposal is: {:?}", *view, proposal.data.clone());
                     return None;
@@ -219,11 +222,12 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> UpgradeTaskStat
                 // Check if we are the leader.
                 {
                     let view = vote.view_number();
-                    if self.quorum_membership.leader(view) != self.public_key {
+                    if self.quorum_membership.leader(view, self.cur_epoch) != self.public_key {
                         error!(
                             "We are not the leader for view {} are we leader for next view? {}",
                             *view,
-                            self.quorum_membership.leader(view + 1) == self.public_key
+                            self.quorum_membership.leader(view + 1, self.cur_epoch)
+                                == self.public_key
                         );
                         return None;
                     }
@@ -234,6 +238,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> UpgradeTaskStat
                     vote,
                     self.public_key.clone(),
                     &self.quorum_membership,
+                    self.cur_epoch,
                     self.id,
                     &event,
                     &tx,
@@ -260,23 +265,23 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> UpgradeTaskStat
                     && time >= self.start_proposing_time
                     && time < self.stop_proposing_time
                     && !self.upgraded().await
-                    && self
-                        .quorum_membership
-                        .leader(TYPES::Time::new(view + UPGRADE_PROPOSE_OFFSET))
-                        == self.public_key
+                    && self.quorum_membership.leader(
+                        TYPES::View::new(view + UPGRADE_PROPOSE_OFFSET),
+                        self.cur_epoch,
+                    ) == self.public_key
                 {
                     let upgrade_proposal_data = UpgradeProposalData {
                         old_version: V::Base::VERSION,
                         new_version: V::Upgrade::VERSION,
                         new_version_hash: V::UPGRADE_HASH.to_vec(),
-                        old_version_last_view: TYPES::Time::new(view + UPGRADE_BEGIN_OFFSET),
-                        new_version_first_view: TYPES::Time::new(view + UPGRADE_FINISH_OFFSET),
-                        decide_by: TYPES::Time::new(view + UPGRADE_DECIDE_BY_OFFSET),
+                        old_version_last_view: TYPES::View::new(view + UPGRADE_BEGIN_OFFSET),
+                        new_version_first_view: TYPES::View::new(view + UPGRADE_FINISH_OFFSET),
+                        decide_by: TYPES::View::new(view + UPGRADE_DECIDE_BY_OFFSET),
                     };
 
                     let upgrade_proposal = UpgradeProposal {
                         upgrade_proposal: upgrade_proposal_data.clone(),
-                        view_number: TYPES::Time::new(view + UPGRADE_PROPOSE_OFFSET),
+                        view_number: TYPES::View::new(view + UPGRADE_PROPOSE_OFFSET),
                     };
 
                     let signature = TYPES::SignatureKey::sign(
diff --git a/crates/task-impls/src/vid.rs b/crates/task-impls/src/vid.rs
index 105aad46dc..106203bd07 100644
--- a/crates/task-impls/src/vid.rs
+++ b/crates/task-impls/src/vid.rs
@@ -30,7 +30,9 @@ use crate::{
 /// Tracks state of a VID task
 pub struct VidTaskState<TYPES: NodeType, I: NodeImplementation<TYPES>> {
     /// View number this view is executing in.
-    pub cur_view: TYPES::Time,
+    pub cur_view: TYPES::View,
+    /// Epoch number this node is executing in.
+    pub cur_epoch: TYPES::Epoch,
     /// Reference to consensus. Leader will require a read lock on this.
     pub consensus: OuterConsensus<TYPES>,
     /// The underlying network
@@ -42,7 +44,7 @@ pub struct VidTaskState<TYPES: NodeType, I: NodeImplementation<TYPES>> {
     /// Our Private Key
     pub private_key: <TYPES::SignatureKey as SignatureKey>::PrivateKey,
     /// The view and ID of the current vote collection task, if there is one.
-    pub vote_collector: Option<(TYPES::Time, usize, usize)>,
+    pub vote_collector: Option<(TYPES::View, usize, usize)>,
     /// This state's ID
     pub id: u64,
 }
@@ -73,6 +75,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>> VidTaskState<TYPES, I> {
                     Arc::clone(encoded_transactions),
                     &Arc::clone(&self.membership),
                     *view_number,
+                    self.cur_epoch,
                     vid_precompute.clone(),
                 )
                 .await;
diff --git a/crates/task-impls/src/view_sync.rs b/crates/task-impls/src/view_sync.rs
index cc06ed170d..fb00054f88 100644
--- a/crates/task-impls/src/view_sync.rs
+++ b/crates/task-impls/src/view_sync.rs
@@ -62,16 +62,18 @@ pub enum ViewSyncPhase {
 
 /// Type alias for a map from View Number to Relay to Vote Task
 type RelayMap<TYPES, VOTE, CERT, V> = HashMap<
-    <TYPES as NodeType>::Time,
+    <TYPES as NodeType>::View,
     BTreeMap<u64, VoteCollectionTaskState<TYPES, VOTE, CERT, V>>,
 >;
 
 /// Main view sync task state
 pub struct ViewSyncTaskState<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> {
     /// View HotShot is currently in
-    pub current_view: TYPES::Time,
+    pub current_view: TYPES::View,
     /// View HotShot wishes to be in
-    pub next_view: TYPES::Time,
+    pub next_view: TYPES::View,
+    /// Epoch HotShot is currently in
+    pub current_epoch: TYPES::Epoch,
     /// The underlying network
     pub network: Arc<I::Network>,
     /// Membership for the quorum
@@ -87,7 +89,7 @@ pub struct ViewSyncTaskState<TYPES: NodeType, I: NodeImplementation<TYPES>, V: V
     pub num_timeouts_tracked: u64,
 
     /// Map of running replica tasks
-    pub replica_task_map: RwLock<HashMap<TYPES::Time, ViewSyncReplicaTaskState<TYPES, I, V>>>,
+    pub replica_task_map: RwLock<HashMap<TYPES::View, ViewSyncReplicaTaskState<TYPES, I, V>>>,
 
     /// Map of pre-commit vote accumulates for the relay
     pub pre_commit_relay_map: RwLock<
@@ -105,7 +107,7 @@ pub struct ViewSyncTaskState<TYPES: NodeType, I: NodeImplementation<TYPES>, V: V
     pub view_sync_timeout: Duration,
 
     /// Last view we garbage collected old tasks
-    pub last_garbage_collected_view: TYPES::Time,
+    pub last_garbage_collected_view: TYPES::View,
 
     /// Lock for a decided upgrade
     pub upgrade_lock: UpgradeLock<TYPES, V>,
@@ -136,9 +138,11 @@ pub struct ViewSyncReplicaTaskState<TYPES: NodeType, I: NodeImplementation<TYPES
     /// Timeout for view sync rounds
     pub view_sync_timeout: Duration,
     /// Current round HotShot is in
-    pub current_view: TYPES::Time,
+    pub current_view: TYPES::View,
     /// Round HotShot wishes to be in
-    pub next_view: TYPES::Time,
+    pub next_view: TYPES::View,
+    /// Current epoch HotShot is in
+    pub current_epoch: TYPES::Epoch,
     /// The relay index we are currently on
     pub relay: u64,
     /// Whether we have seen a finalized certificate
@@ -189,7 +193,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> ViewSyncTaskSta
     pub async fn send_to_or_create_replica(
         &mut self,
         event: Arc<HotShotEvent<TYPES>>,
-        view: TYPES::Time,
+        view: TYPES::View,
         sender: &Sender<Arc<HotShotEvent<TYPES>>>,
     ) {
         // This certificate is old, we can throw it away
@@ -221,6 +225,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> ViewSyncTaskSta
         let mut replica_state: ViewSyncReplicaTaskState<TYPES, I, V> = ViewSyncReplicaTaskState {
             current_view: view,
             next_view: view,
+            current_epoch: self.current_epoch,
             relay: 0,
             finalized: false,
             sent_view_change_event: false,
@@ -299,7 +304,11 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> ViewSyncTaskSta
                 }
 
                 // We do not have a relay task already running, so start one
-                if self.membership.leader(vote_view + relay) != self.public_key {
+                if self
+                    .membership
+                    .leader(vote_view + relay, self.current_epoch)
+                    != self.public_key
+                {
                     debug!("View sync vote sent to wrong leader");
                     return;
                 }
@@ -308,6 +317,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> ViewSyncTaskSta
                     public_key: self.public_key.clone(),
                     membership: Arc::clone(&self.membership),
                     view: vote_view,
+                    epoch: self.current_epoch,
                     id: self.id,
                 };
                 let vote_collector =
@@ -337,7 +347,11 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> ViewSyncTaskSta
                 }
 
                 // We do not have a relay task already running, so start one
-                if self.membership.leader(vote_view + relay) != self.public_key {
+                if self
+                    .membership
+                    .leader(vote_view + relay, self.current_epoch)
+                    != self.public_key
+                {
                     debug!("View sync vote sent to wrong leader");
                     return;
                 }
@@ -346,6 +360,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> ViewSyncTaskSta
                     public_key: self.public_key.clone(),
                     membership: Arc::clone(&self.membership),
                     view: vote_view,
+                    epoch: self.current_epoch,
                     id: self.id,
                 };
                 let vote_collector =
@@ -375,7 +390,11 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> ViewSyncTaskSta
                 }
 
                 // We do not have a relay task already running, so start one
-                if self.membership.leader(vote_view + relay) != self.public_key {
+                if self
+                    .membership
+                    .leader(vote_view + relay, self.current_epoch)
+                    != self.public_key
+                {
                     debug!("View sync vote sent to wrong leader");
                     return;
                 }
@@ -384,6 +403,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> ViewSyncTaskSta
                     public_key: self.public_key.clone(),
                     membership: Arc::clone(&self.membership),
                     view: vote_view,
+                    epoch: self.current_epoch,
                     id: self.id,
                 };
                 let vote_collector =
@@ -395,7 +415,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> ViewSyncTaskSta
             }
 
             &HotShotEvent::ViewChange(new_view) => {
-                let new_view = TYPES::Time::new(*new_view);
+                let new_view = TYPES::View::new(*new_view);
                 if self.current_view < new_view {
                     debug!(
                         "Change from view {} to view {} in view sync task",
@@ -414,19 +434,19 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> ViewSyncTaskSta
                         self.replica_task_map
                             .write()
                             .await
-                            .remove_entry(&TYPES::Time::new(i));
+                            .remove_entry(&TYPES::View::new(i));
                         self.pre_commit_relay_map
                             .write()
                             .await
-                            .remove_entry(&TYPES::Time::new(i));
+                            .remove_entry(&TYPES::View::new(i));
                         self.commit_relay_map
                             .write()
                             .await
-                            .remove_entry(&TYPES::Time::new(i));
+                            .remove_entry(&TYPES::View::new(i));
                         self.finalize_relay_map
                             .write()
                             .await
-                            .remove_entry(&TYPES::Time::new(i));
+                            .remove_entry(&TYPES::View::new(i));
                     }
 
                     self.last_garbage_collected_view = self.current_view - 1;
@@ -434,12 +454,12 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> ViewSyncTaskSta
             }
             &HotShotEvent::Timeout(view_number) => {
                 // This is an old timeout and we can ignore it
-                if view_number <= TYPES::Time::new(*self.current_view) {
+                if view_number <= TYPES::View::new(*self.current_view) {
                     return;
                 }
 
                 self.num_timeouts_tracked += 1;
-                let leader = self.membership.leader(view_number);
+                let leader = self.membership.leader(view_number, self.current_epoch);
                 warn!(
                     %leader,
                     leader_mnemonic = cdn_proto::util::mnemonic(&leader),
@@ -465,7 +485,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions> ViewSyncTaskSta
                     // If this is the first timeout we've seen advance to the next view
                     self.current_view = view_number;
                     broadcast_event(
-                        Arc::new(HotShotEvent::ViewChange(TYPES::Time::new(
+                        Arc::new(HotShotEvent::ViewChange(TYPES::View::new(
                             *self.current_view,
                         ))),
                         &event_stream,
@@ -502,7 +522,11 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>
 
                 // If certificate is not valid, return current state
                 if !certificate
-                    .is_valid_cert(self.membership.as_ref(), &self.upgrade_lock)
+                    .is_valid_cert(
+                        self.membership.as_ref(),
+                        self.current_epoch,
+                        &self.upgrade_lock,
+                    )
                     .await
                 {
                     error!("Not valid view sync cert! {:?}", certificate.data());
@@ -561,7 +585,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>
 
                         broadcast_event(
                             Arc::new(HotShotEvent::ViewSyncTimeout(
-                                TYPES::Time::new(*next_view),
+                                TYPES::View::new(*next_view),
                                 relay,
                                 phase,
                             )),
@@ -584,7 +608,11 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>
 
                 // If certificate is not valid, return current state
                 if !certificate
-                    .is_valid_cert(self.membership.as_ref(), &self.upgrade_lock)
+                    .is_valid_cert(
+                        self.membership.as_ref(),
+                        self.current_epoch,
+                        &self.upgrade_lock,
+                    )
                     .await
                 {
                     error!("Not valid view sync cert! {:?}", certificate.data());
@@ -655,7 +683,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>
                         );
                         broadcast_event(
                             Arc::new(HotShotEvent::ViewSyncTimeout(
-                                TYPES::Time::new(*next_view),
+                                TYPES::View::new(*next_view),
                                 relay,
                                 phase,
                             )),
@@ -676,7 +704,11 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>
 
                 // If certificate is not valid, return current state
                 if !certificate
-                    .is_valid_cert(self.membership.as_ref(), &self.upgrade_lock)
+                    .is_valid_cert(
+                        self.membership.as_ref(),
+                        self.current_epoch,
+                        &self.upgrade_lock,
+                    )
                     .await
                 {
                     error!("Not valid view sync cert! {:?}", certificate.data());
@@ -708,7 +740,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>
 
             HotShotEvent::ViewSyncTrigger(view_number) => {
                 let view_number = *view_number;
-                if self.next_view != TYPES::Time::new(*view_number) {
+                if self.next_view != TYPES::View::new(*view_number) {
                     error!("Unexpected view number to triger view sync");
                     return None;
                 }
@@ -748,7 +780,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>
                         warn!("Vote sending timed out in ViewSyncTrigger");
                         broadcast_event(
                             Arc::new(HotShotEvent::ViewSyncTimeout(
-                                TYPES::Time::new(*next_view),
+                                TYPES::View::new(*next_view),
                                 relay,
                                 ViewSyncPhase::None,
                             )),
@@ -764,7 +796,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>
             HotShotEvent::ViewSyncTimeout(round, relay, last_seen_certificate) => {
                 let round = *round;
                 // Shouldn't ever receive a timeout for a relay higher than ours
-                if TYPES::Time::new(*round) == self.next_view && *relay == self.relay {
+                if TYPES::View::new(*round) == self.next_view && *relay == self.relay {
                     if let Some(timeout_task) = self.timeout_task.take() {
                         cancel_task(timeout_task).await;
                     }
@@ -817,7 +849,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>
                             );
                             broadcast_event(
                                 Arc::new(HotShotEvent::ViewSyncTimeout(
-                                    TYPES::Time::new(*next_view),
+                                    TYPES::View::new(*next_view),
                                     relay,
                                     last_cert,
                                 )),
diff --git a/crates/task-impls/src/vote_collection.rs b/crates/task-impls/src/vote_collection.rs
index a7ec9cd7e9..533a96b719 100644
--- a/crates/task-impls/src/vote_collection.rs
+++ b/crates/task-impls/src/vote_collection.rs
@@ -39,7 +39,7 @@ use crate::{
 
 /// Alias for a map of Vote Collectors
 pub type VoteCollectorsMap<TYPES, VOTE, CERT, V> =
-    BTreeMap<<TYPES as NodeType>::Time, VoteCollectionTaskState<TYPES, VOTE, CERT, V>>;
+    BTreeMap<<TYPES as NodeType>::View, VoteCollectionTaskState<TYPES, VOTE, CERT, V>>;
 
 /// Task state for collecting votes of one type and emitting a certificate
 pub struct VoteCollectionTaskState<
@@ -58,7 +58,10 @@ pub struct VoteCollectionTaskState<
     pub accumulator: Option<VoteAccumulator<TYPES, VOTE, CERT, V>>,
 
     /// The view which we are collecting votes for
-    pub view: TYPES::Time,
+    pub view: TYPES::View,
+
+    /// The epoch which we are collecting votes for
+    pub epoch: TYPES::Epoch,
 
     /// Node id
     pub id: u64,
@@ -71,8 +74,8 @@ pub trait AggregatableVote<
     CERT: Certificate<TYPES, Voteable = VOTE::Commitment>,
 >
 {
-    /// return the leader for this votes
-    fn leader(&self, membership: &TYPES::Membership) -> TYPES::SignatureKey;
+    /// return the leader for this votes in the given epoch
+    fn leader(&self, membership: &TYPES::Membership, epoch: TYPES::Epoch) -> TYPES::SignatureKey;
 
     /// return the Hotshot event for the completion of this CERT
     fn make_cert_event(certificate: CERT, key: &TYPES::SignatureKey) -> HotShotEvent<TYPES>;
@@ -93,7 +96,7 @@ impl<
         vote: &VOTE,
         event_stream: &Sender<Arc<HotShotEvent<TYPES>>>,
     ) -> Option<HotShotTaskCompleted> {
-        if vote.leader(&self.membership) != self.public_key {
+        if vote.leader(&self.membership, self.epoch) != self.public_key {
             error!("Received vote for a view in which we were not the leader.");
             return None;
         }
@@ -108,7 +111,10 @@ impl<
         }
 
         let accumulator = self.accumulator.as_mut()?;
-        match accumulator.accumulate(vote, &self.membership).await {
+        match accumulator
+            .accumulate(vote, &self.membership, self.epoch)
+            .await
+        {
             Either::Left(()) => None,
             Either::Right(cert) => {
                 debug!("Certificate Formed! {:?}", cert);
@@ -151,7 +157,9 @@ pub struct AccumulatorInfo<TYPES: NodeType> {
     /// Membership we are accumulation votes for
     pub membership: Arc<TYPES::Membership>,
     /// View of the votes we are collecting
-    pub view: TYPES::Time,
+    pub view: TYPES::View,
+    /// Epoch of the votes we are collecting
+    pub epoch: TYPES::Epoch,
     /// This nodes id
     pub id: u64,
 }
@@ -192,6 +200,7 @@ where
         public_key: info.public_key.clone(),
         accumulator: Some(new_accumulator),
         view: info.view,
+        epoch: info.epoch,
         id: info.id,
     };
 
@@ -217,6 +226,7 @@ pub async fn handle_vote<
     vote: &VOTE,
     public_key: TYPES::SignatureKey,
     membership: &Arc<TYPES::Membership>,
+    epoch: TYPES::Epoch,
     id: u64,
     event: &Arc<HotShotEvent<TYPES>>,
     event_stream: &Sender<Arc<HotShotEvent<TYPES>>>,
@@ -231,6 +241,7 @@ pub async fn handle_vote<
                 public_key,
                 membership: Arc::clone(membership),
                 view: vote.view_number(),
+                epoch,
                 id,
             };
             if let Some(collector) = create_vote_accumulator(
@@ -292,8 +303,8 @@ type ViewSyncFinalizeVoteState<TYPES, V> = VoteCollectionTaskState<
 impl<TYPES: NodeType> AggregatableVote<TYPES, QuorumVote<TYPES>, QuorumCertificate<TYPES>>
     for QuorumVote<TYPES>
 {
-    fn leader(&self, membership: &TYPES::Membership) -> TYPES::SignatureKey {
-        membership.leader(self.view_number() + 1)
+    fn leader(&self, membership: &TYPES::Membership, epoch: TYPES::Epoch) -> TYPES::SignatureKey {
+        membership.leader(self.view_number() + 1, epoch)
     }
     fn make_cert_event(
         certificate: QuorumCertificate<TYPES>,
@@ -306,8 +317,8 @@ impl<TYPES: NodeType> AggregatableVote<TYPES, QuorumVote<TYPES>, QuorumCertifica
 impl<TYPES: NodeType> AggregatableVote<TYPES, UpgradeVote<TYPES>, UpgradeCertificate<TYPES>>
     for UpgradeVote<TYPES>
 {
-    fn leader(&self, membership: &TYPES::Membership) -> TYPES::SignatureKey {
-        membership.leader(self.view_number())
+    fn leader(&self, membership: &TYPES::Membership, epoch: TYPES::Epoch) -> TYPES::SignatureKey {
+        membership.leader(self.view_number(), epoch)
     }
     fn make_cert_event(
         certificate: UpgradeCertificate<TYPES>,
@@ -320,8 +331,8 @@ impl<TYPES: NodeType> AggregatableVote<TYPES, UpgradeVote<TYPES>, UpgradeCertifi
 impl<TYPES: NodeType> AggregatableVote<TYPES, DaVote<TYPES>, DaCertificate<TYPES>>
     for DaVote<TYPES>
 {
-    fn leader(&self, membership: &TYPES::Membership) -> TYPES::SignatureKey {
-        membership.leader(self.view_number())
+    fn leader(&self, membership: &TYPES::Membership, epoch: TYPES::Epoch) -> TYPES::SignatureKey {
+        membership.leader(self.view_number(), epoch)
     }
     fn make_cert_event(
         certificate: DaCertificate<TYPES>,
@@ -334,8 +345,8 @@ impl<TYPES: NodeType> AggregatableVote<TYPES, DaVote<TYPES>, DaCertificate<TYPES
 impl<TYPES: NodeType> AggregatableVote<TYPES, TimeoutVote<TYPES>, TimeoutCertificate<TYPES>>
     for TimeoutVote<TYPES>
 {
-    fn leader(&self, membership: &TYPES::Membership) -> TYPES::SignatureKey {
-        membership.leader(self.view_number() + 1)
+    fn leader(&self, membership: &TYPES::Membership, epoch: TYPES::Epoch) -> TYPES::SignatureKey {
+        membership.leader(self.view_number() + 1, epoch)
     }
     fn make_cert_event(
         certificate: TimeoutCertificate<TYPES>,
@@ -349,8 +360,8 @@ impl<TYPES: NodeType>
     AggregatableVote<TYPES, ViewSyncCommitVote<TYPES>, ViewSyncCommitCertificate2<TYPES>>
     for ViewSyncCommitVote<TYPES>
 {
-    fn leader(&self, membership: &TYPES::Membership) -> TYPES::SignatureKey {
-        membership.leader(self.date().round + self.date().relay)
+    fn leader(&self, membership: &TYPES::Membership, epoch: TYPES::Epoch) -> TYPES::SignatureKey {
+        membership.leader(self.date().round + self.date().relay, epoch)
     }
     fn make_cert_event(
         certificate: ViewSyncCommitCertificate2<TYPES>,
@@ -364,8 +375,8 @@ impl<TYPES: NodeType>
     AggregatableVote<TYPES, ViewSyncPreCommitVote<TYPES>, ViewSyncPreCommitCertificate2<TYPES>>
     for ViewSyncPreCommitVote<TYPES>
 {
-    fn leader(&self, membership: &TYPES::Membership) -> TYPES::SignatureKey {
-        membership.leader(self.date().round + self.date().relay)
+    fn leader(&self, membership: &TYPES::Membership, epoch: TYPES::Epoch) -> TYPES::SignatureKey {
+        membership.leader(self.date().round + self.date().relay, epoch)
     }
     fn make_cert_event(
         certificate: ViewSyncPreCommitCertificate2<TYPES>,
@@ -379,8 +390,8 @@ impl<TYPES: NodeType>
     AggregatableVote<TYPES, ViewSyncFinalizeVote<TYPES>, ViewSyncFinalizeCertificate2<TYPES>>
     for ViewSyncFinalizeVote<TYPES>
 {
-    fn leader(&self, membership: &TYPES::Membership) -> TYPES::SignatureKey {
-        membership.leader(self.date().round + self.date().relay)
+    fn leader(&self, membership: &TYPES::Membership, epoch: TYPES::Epoch) -> TYPES::SignatureKey {
+        membership.leader(self.date().round + self.date().relay, epoch)
     }
     fn make_cert_event(
         certificate: ViewSyncFinalizeCertificate2<TYPES>,
diff --git a/crates/testing/src/byzantine/byzantine_behaviour.rs b/crates/testing/src/byzantine/byzantine_behaviour.rs
index beab8b5ae6..825108e48b 100644
--- a/crates/testing/src/byzantine/byzantine_behaviour.rs
+++ b/crates/testing/src/byzantine/byzantine_behaviour.rs
@@ -116,7 +116,7 @@ pub struct DishonestLeader<TYPES: NodeType> {
     /// How far back to look for a QC
     pub view_look_back: usize,
     /// Shared state of all view numbers we send bad proposal at
-    pub dishonest_proposal_view_numbers: Arc<RwLock<HashSet<TYPES::Time>>>,
+    pub dishonest_proposal_view_numbers: Arc<RwLock<HashSet<TYPES::View>>>,
 }
 
 /// Add method that will handle `QuorumProposalSend` events
@@ -246,7 +246,7 @@ pub struct ViewDelay<TYPES: NodeType> {
     /// How many views the node will be delayed
     pub number_of_views_to_delay: u64,
     /// A map that is from view number to vector of events
-    pub events_for_view: HashMap<TYPES::Time, Vec<HotShotEvent<TYPES>>>,
+    pub events_for_view: HashMap<TYPES::View, Vec<HotShotEvent<TYPES>>>,
     /// Specify which view number to stop delaying
     pub stop_view_delay_at_view_number: u64,
 }
@@ -271,7 +271,7 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES> + std::fmt::Debug, V: Version
             if view_diff > 0 {
                 return match self
                     .events_for_view
-                    .remove(&<TYPES as NodeType>::Time::new(view_diff))
+                    .remove(&<TYPES as NodeType>::View::new(view_diff))
                 {
                     Some(lookback_events) => lookback_events.clone(),
                     // we have already return all received events for this view
@@ -346,7 +346,8 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES> + std::fmt::Debug, V: Version
     ) {
         let network_state: NetworkEventTaskState<_, V, _, _> = NetworkEventTaskState {
             network,
-            view: TYPES::Time::genesis(),
+            view: TYPES::View::genesis(),
+            epoch: TYPES::Epoch::genesis(),
             quorum_membership,
             da_membership,
             storage: Arc::clone(&handle.storage()),
@@ -375,7 +376,7 @@ pub struct DishonestVoter<TYPES: NodeType> {
     /// Collect all votes the node sends
     pub votes_sent: Vec<QuorumVote<TYPES>>,
     /// Shared state with views numbers that leaders were dishonest at
-    pub dishonest_proposal_view_numbers: Arc<RwLock<HashSet<TYPES::Time>>>,
+    pub dishonest_proposal_view_numbers: Arc<RwLock<HashSet<TYPES::View>>>,
 }
 
 #[async_trait]
diff --git a/crates/testing/src/consistency_task.rs b/crates/testing/src/consistency_task.rs
index 3cb04f65c1..0d78c4d12c 100644
--- a/crates/testing/src/consistency_task.rs
+++ b/crates/testing/src/consistency_task.rs
@@ -24,10 +24,10 @@ use crate::{
 };
 
 /// Map from views to leaves for a single node, allowing multiple leaves for each view (because the node may a priori send us multiple leaves for a given view).
-pub type NodeMap<TYPES> = BTreeMap<<TYPES as NodeType>::Time, Vec<Leaf<TYPES>>>;
+pub type NodeMap<TYPES> = BTreeMap<<TYPES as NodeType>::View, Vec<Leaf<TYPES>>>;
 
 /// A sanitized map from views to leaves for a single node, with only a single leaf per view.
-pub type NodeMapSanitized<TYPES> = BTreeMap<<TYPES as NodeType>::Time, Leaf<TYPES>>;
+pub type NodeMapSanitized<TYPES> = BTreeMap<<TYPES as NodeType>::View, Leaf<TYPES>>;
 
 /// Validate that the `NodeMap` only has a single leaf per view.
 fn sanitize_node_map<TYPES: NodeType>(
@@ -68,7 +68,7 @@ async fn validate_node_map<TYPES: NodeType, V: Versions>(
         .map(|((a, b), c)| (a, b, c));
 
     let mut decided_upgrade_certificate = None;
-    let mut view_decided = TYPES::Time::new(0);
+    let mut view_decided = TYPES::View::new(0);
 
     for (grandparent, _parent, child) in leaf_triples {
         if let Some(cert) = grandparent.upgrade_certificate() {
@@ -144,7 +144,7 @@ fn sanitize_network_map<TYPES: NodeType>(
     Ok(result)
 }
 
-pub type ViewMap<TYPES> = BTreeMap<<TYPES as NodeType>::Time, BTreeMap<usize, Leaf<TYPES>>>;
+pub type ViewMap<TYPES> = BTreeMap<<TYPES as NodeType>::View, BTreeMap<usize, Leaf<TYPES>>>;
 
 // Invert the network map by interchanging the roles of the node_id and view number.
 //
@@ -171,7 +171,7 @@ async fn invert_network_map<TYPES: NodeType, V: Versions>(
 }
 
 /// A view map, sanitized to have exactly one leaf per view.
-pub type ViewMapSanitized<TYPES> = BTreeMap<<TYPES as NodeType>::Time, Leaf<TYPES>>;
+pub type ViewMapSanitized<TYPES> = BTreeMap<<TYPES as NodeType>::View, Leaf<TYPES>>;
 
 fn sanitize_view_map<TYPES: NodeType>(
     view_map: &ViewMap<TYPES>,
diff --git a/crates/testing/src/helpers.rs b/crates/testing/src/helpers.rs
index 54eab9d4fa..842ef3e538 100644
--- a/crates/testing/src/helpers.rs
+++ b/crates/testing/src/helpers.rs
@@ -150,7 +150,8 @@ pub async fn build_cert<
 >(
     data: DATAType,
     membership: &TYPES::Membership,
-    view: TYPES::Time,
+    view: TYPES::View,
+    epoch: TYPES::Epoch,
     public_key: &TYPES::SignatureKey,
     private_key: &<TYPES::SignatureKey as SignatureKey>::PrivateKey,
     upgrade_lock: &UpgradeLock<TYPES, V>,
@@ -159,6 +160,7 @@ pub async fn build_cert<
         &data,
         membership,
         view,
+        epoch,
         upgrade_lock,
     )
     .await;
@@ -214,10 +216,11 @@ pub async fn build_assembled_sig<
 >(
     data: &DATAType,
     membership: &TYPES::Membership,
-    view: TYPES::Time,
+    view: TYPES::View,
+    epoch: TYPES::Epoch,
     upgrade_lock: &UpgradeLock<TYPES, V>,
 ) -> <TYPES::SignatureKey as SignatureKey>::QcType {
-    let stake_table = membership.stake_table();
+    let stake_table = membership.stake_table(epoch);
     let real_qc_pp: <TYPES::SignatureKey as SignatureKey>::QcParams =
         <TYPES::SignatureKey as SignatureKey>::public_parameter(
             stake_table.clone(),
@@ -272,18 +275,23 @@ pub fn key_pair_for_id<TYPES: NodeType>(
 #[must_use]
 pub fn vid_scheme_from_view_number<TYPES: NodeType>(
     membership: &TYPES::Membership,
-    view_number: TYPES::Time,
+    view_number: TYPES::View,
+    epoch_number: TYPES::Epoch,
 ) -> VidSchemeType {
-    let num_storage_nodes = membership.committee_members(view_number).len();
+    let num_storage_nodes = membership
+        .committee_members(view_number, epoch_number)
+        .len();
     vid_scheme(num_storage_nodes)
 }
 
 pub fn vid_payload_commitment<TYPES: NodeType>(
     quorum_membership: &<TYPES as NodeType>::Membership,
-    view_number: TYPES::Time,
+    view_number: TYPES::View,
+    epoch_number: TYPES::Epoch,
     transactions: Vec<TestTransaction>,
 ) -> VidCommitment {
-    let mut vid = vid_scheme_from_view_number::<TYPES>(quorum_membership, view_number);
+    let mut vid =
+        vid_scheme_from_view_number::<TYPES>(quorum_membership, view_number, epoch_number);
     let encoded_transactions = TestTransaction::encode(&transactions);
     let vid_disperse = vid.disperse(&encoded_transactions).unwrap();
 
@@ -293,19 +301,24 @@ pub fn vid_payload_commitment<TYPES: NodeType>(
 pub fn da_payload_commitment<TYPES: NodeType>(
     quorum_membership: &<TYPES as NodeType>::Membership,
     transactions: Vec<TestTransaction>,
+    epoch_number: TYPES::Epoch,
 ) -> VidCommitment {
     let encoded_transactions = TestTransaction::encode(&transactions);
 
-    vid_commitment(&encoded_transactions, quorum_membership.total_nodes())
+    vid_commitment(
+        &encoded_transactions,
+        quorum_membership.total_nodes(epoch_number),
+    )
 }
 
 pub fn build_payload_commitment<TYPES: NodeType>(
     membership: &<TYPES as NodeType>::Membership,
-    view: TYPES::Time,
+    view: TYPES::View,
+    epoch: TYPES::Epoch,
 ) -> <VidSchemeType as VidScheme>::Commit {
     // Make some empty encoded transactions, we just care about having a commitment handy for the
     // later calls. We need the VID commitment to be able to propose later.
-    let mut vid = vid_scheme_from_view_number::<TYPES>(membership, view);
+    let mut vid = vid_scheme_from_view_number::<TYPES>(membership, view, epoch);
     let encoded_transactions = Vec::new();
     vid.commit_only(&encoded_transactions).unwrap()
 }
@@ -313,17 +326,20 @@ pub fn build_payload_commitment<TYPES: NodeType>(
 /// TODO: <https://github.com/EspressoSystems/HotShot/issues/2821>
 pub fn build_vid_proposal<TYPES: NodeType>(
     quorum_membership: &<TYPES as NodeType>::Membership,
-    view_number: TYPES::Time,
+    view_number: TYPES::View,
+    epoch_number: TYPES::Epoch,
     transactions: Vec<TestTransaction>,
     private_key: &<TYPES::SignatureKey as SignatureKey>::PrivateKey,
 ) -> VidProposal<TYPES> {
-    let mut vid = vid_scheme_from_view_number::<TYPES>(quorum_membership, view_number);
+    let mut vid =
+        vid_scheme_from_view_number::<TYPES>(quorum_membership, view_number, epoch_number);
     let encoded_transactions = TestTransaction::encode(&transactions);
 
     let vid_disperse = VidDisperse::from_membership(
         view_number,
         vid.disperse(&encoded_transactions).unwrap(),
         quorum_membership,
+        epoch_number,
     );
 
     let signature =
@@ -348,10 +364,12 @@ pub fn build_vid_proposal<TYPES: NodeType>(
     )
 }
 
+#[allow(clippy::too_many_arguments)]
 pub async fn build_da_certificate<TYPES: NodeType, V: Versions>(
     quorum_membership: &<TYPES as NodeType>::Membership,
     da_membership: &<TYPES as NodeType>::Membership,
-    view_number: TYPES::Time,
+    view_number: TYPES::View,
+    epoch_number: TYPES::Epoch,
     transactions: Vec<TestTransaction>,
     public_key: &TYPES::SignatureKey,
     private_key: &<TYPES::SignatureKey as SignatureKey>::PrivateKey,
@@ -359,8 +377,10 @@ pub async fn build_da_certificate<TYPES: NodeType, V: Versions>(
 ) -> DaCertificate<TYPES> {
     let encoded_transactions = TestTransaction::encode(&transactions);
 
-    let da_payload_commitment =
-        vid_commitment(&encoded_transactions, quorum_membership.total_nodes());
+    let da_payload_commitment = vid_commitment(
+        &encoded_transactions,
+        quorum_membership.total_nodes(epoch_number),
+    );
 
     let da_data = DaData {
         payload_commit: da_payload_commitment,
@@ -370,6 +390,7 @@ pub async fn build_da_certificate<TYPES: NodeType, V: Versions>(
         da_data,
         da_membership,
         view_number,
+        epoch_number,
         public_key,
         private_key,
         upgrade_lock,
diff --git a/crates/testing/src/overall_safety_task.rs b/crates/testing/src/overall_safety_task.rs
index 3cbe364517..979c2c2a04 100644
--- a/crates/testing/src/overall_safety_task.rs
+++ b/crates/testing/src/overall_safety_task.rs
@@ -61,12 +61,12 @@ pub enum OverallSafetyTaskErr<TYPES: NodeType> {
     NotEnoughDecides { got: usize, expected: usize },
 
     #[error("Too many view failures: {0:?}")]
-    TooManyFailures(HashSet<TYPES::Time>),
+    TooManyFailures(HashSet<TYPES::View>),
 
     #[error("Inconsistent failed views: expected: {expected_failed_views:?}, actual: {actual_failed_views:?}")]
     InconsistentFailedViews {
-        expected_failed_views: Vec<TYPES::Time>,
-        actual_failed_views: HashSet<TYPES::Time>,
+        expected_failed_views: Vec<TYPES::View>,
+        actual_failed_views: HashSet<TYPES::View>,
     },
     #[error(
         "Not enough round results: results_count: {results_count}, views_count: {views_count}"
@@ -97,7 +97,7 @@ pub struct OverallSafetyTask<TYPES: NodeType, I: TestableNodeImplementation<TYPE
 impl<TYPES: NodeType, I: TestableNodeImplementation<TYPES>, V: Versions>
     OverallSafetyTask<TYPES, I, V>
 {
-    async fn handle_view_failure(&mut self, num_failed_views: usize, view_number: TYPES::Time) {
+    async fn handle_view_failure(&mut self, num_failed_views: usize, view_number: TYPES::View) {
         let expected_views_to_fail = &mut self.properties.expected_views_to_fail;
 
         self.ctx.failed_views.insert(view_number);
@@ -155,7 +155,7 @@ impl<TYPES: NodeType, I: TestableNodeImplementation<TYPES>, V: Versions> TestTas
                 block_size: maybe_block_size,
             } => {
                 // Skip the genesis leaf.
-                if leaf_chain.last().unwrap().leaf.view_number() == TYPES::Time::genesis() {
+                if leaf_chain.last().unwrap().leaf.view_number() == TYPES::View::genesis() {
                     return Ok(());
                 }
                 let paired_up = (leaf_chain.to_vec(), (*qc).clone());
@@ -364,18 +364,18 @@ impl<TYPES: NodeType> Default for RoundCtx<TYPES> {
 pub struct RoundCtx<TYPES: NodeType> {
     /// results from previous rounds
     /// view number -> round result
-    pub round_results: HashMap<TYPES::Time, RoundResult<TYPES>>,
+    pub round_results: HashMap<TYPES::View, RoundResult<TYPES>>,
     /// during the run view refactor
-    pub failed_views: HashSet<TYPES::Time>,
+    pub failed_views: HashSet<TYPES::View>,
     /// successful views
-    pub successful_views: HashSet<TYPES::Time>,
+    pub successful_views: HashSet<TYPES::View>,
 }
 
 impl<TYPES: NodeType> RoundCtx<TYPES> {
     /// inserts an error into the context
     pub fn insert_error_to_context(
         &mut self,
-        view_number: TYPES::Time,
+        view_number: TYPES::View,
         idx: usize,
         error: Arc<HotShotError<TYPES>>,
     ) {
@@ -569,7 +569,7 @@ pub struct OverallSafetyPropertiesDescription<TYPES: NodeType> {
     /// required to mark view as successful
     pub threshold_calculator: Arc<dyn Fn(usize, usize) -> usize + Send + Sync>,
     /// pass in the views that we expect to fail
-    pub expected_views_to_fail: HashMap<TYPES::Time, bool>,
+    pub expected_views_to_fail: HashMap<TYPES::View, bool>,
 }
 
 impl<TYPES: NodeType> std::fmt::Debug for OverallSafetyPropertiesDescription<TYPES> {
diff --git a/crates/testing/src/spinning_task.rs b/crates/testing/src/spinning_task.rs
index eafc52fbb2..5593a4336e 100644
--- a/crates/testing/src/spinning_task.rs
+++ b/crates/testing/src/spinning_task.rs
@@ -58,9 +58,9 @@ pub struct SpinningTask<
     /// late start nodes
     pub(crate) late_start: HashMap<u64, LateStartNode<TYPES, I, V>>,
     /// time based changes
-    pub(crate) changes: BTreeMap<TYPES::Time, Vec<ChangeNode>>,
+    pub(crate) changes: BTreeMap<TYPES::View, Vec<ChangeNode>>,
     /// most recent view seen by spinning task
-    pub(crate) latest_view: Option<TYPES::Time>,
+    pub(crate) latest_view: Option<TYPES::View>,
     /// Last decided leaf that can be used as the anchor leaf to initialize the node.
     pub(crate) last_decided_leaf: Leaf<TYPES>,
     /// Highest qc seen in the test for restarting nodes
@@ -155,8 +155,8 @@ where
                                             self.last_decided_leaf.clone(),
                                             TestInstanceState::new(self.async_delay_config.clone()),
                                             None,
-                                            TYPES::Time::genesis(),
-                                            TYPES::Time::genesis(),
+                                            TYPES::View::genesis(),
+                                            TYPES::View::genesis(),
                                             BTreeMap::new(),
                                             self.high_qc.clone(),
                                             None,
diff --git a/crates/testing/src/test_builder.rs b/crates/testing/src/test_builder.rs
index 2a7414475f..64d16ede22 100644
--- a/crates/testing/src/test_builder.rs
+++ b/crates/testing/src/test_builder.rs
@@ -529,6 +529,7 @@ where
             stop_proposing_time: 0,
             start_voting_time: u64::MAX,
             stop_voting_time: 0,
+            epoch_height: 0,
         };
         let TimingData {
             next_view_timeout,
diff --git a/crates/testing/src/test_runner.rs b/crates/testing/src/test_runner.rs
index 221f43ced6..cb2c8119ed 100644
--- a/crates/testing/src/test_runner.rs
+++ b/crates/testing/src/test_runner.rs
@@ -170,10 +170,10 @@ where
 
         // add spinning task
         // map spinning to view
-        let mut changes: BTreeMap<TYPES::Time, Vec<ChangeNode>> = BTreeMap::new();
+        let mut changes: BTreeMap<TYPES::View, Vec<ChangeNode>> = BTreeMap::new();
         for (view, mut change) in spinning_changes {
             changes
-                .entry(TYPES::Time::new(view))
+                .entry(TYPES::View::new(view))
                 .or_insert_with(Vec::new)
                 .append(&mut change);
         }
diff --git a/crates/testing/src/view_generator.rs b/crates/testing/src/view_generator.rs
index 315ac2d5e8..dcaedd5dc1 100644
--- a/crates/testing/src/view_generator.rs
+++ b/crates/testing/src/view_generator.rs
@@ -12,6 +12,9 @@ use std::{
     task::{Context, Poll},
 };
 
+use crate::helpers::{
+    build_cert, build_da_certificate, build_vid_proposal, da_payload_commitment, key_pair_for_id,
+};
 use futures::{FutureExt, Stream};
 use hotshot::types::{BLSPubKey, SignatureKey, SystemContextHandle};
 use hotshot_example_types::{
@@ -19,6 +22,7 @@ use hotshot_example_types::{
     node_types::{MemoryImpl, TestTypes, TestVersions},
     state_types::{TestInstanceState, TestValidatedState},
 };
+use hotshot_types::data::EpochNumber;
 use hotshot_types::{
     data::{
         DaProposal, Leaf, QuorumProposal, VidDisperse, VidDisperseShare, ViewChangeEvidence,
@@ -42,16 +46,13 @@ use hotshot_types::{
 use rand::{thread_rng, Rng};
 use sha2::{Digest, Sha256};
 
-use crate::helpers::{
-    build_cert, build_da_certificate, build_vid_proposal, da_payload_commitment, key_pair_for_id,
-};
-
 #[derive(Clone)]
 pub struct TestView {
     pub da_proposal: Proposal<TestTypes, DaProposal<TestTypes>>,
     pub quorum_proposal: Proposal<TestTypes, QuorumProposal<TestTypes>>,
     pub leaf: Leaf<TestTypes>,
     pub view_number: ViewNumber,
+    pub epoch_number: EpochNumber,
     pub quorum_membership: <TestTypes as NodeType>::Membership,
     pub da_membership: <TestTypes as NodeType>::Membership,
     pub vid_disperse: Proposal<TestTypes, VidDisperse<TestTypes>>,
@@ -75,6 +76,7 @@ impl TestView {
         da_membership: &<TestTypes as NodeType>::Membership,
     ) -> Self {
         let genesis_view = ViewNumber::new(1);
+        let genesis_epoch = EpochNumber::new(1);
         let upgrade_lock = UpgradeLock::new();
 
         let transactions = Vec::new();
@@ -97,12 +99,16 @@ impl TestView {
 
         let leader_public_key = public_key;
 
-        let payload_commitment =
-            da_payload_commitment::<TestTypes>(quorum_membership, transactions.clone());
+        let payload_commitment = da_payload_commitment::<TestTypes>(
+            quorum_membership,
+            transactions.clone(),
+            genesis_epoch,
+        );
 
         let (vid_disperse, vid_proposal) = build_vid_proposal(
             quorum_membership,
             genesis_view,
+            genesis_epoch,
             transactions.clone(),
             &private_key,
         );
@@ -111,6 +117,7 @@ impl TestView {
             quorum_membership,
             da_membership,
             genesis_view,
+            genesis_epoch,
             transactions.clone(),
             &public_key,
             &private_key,
@@ -180,6 +187,7 @@ impl TestView {
             quorum_proposal,
             leaf,
             view_number: genesis_view,
+            epoch_number: genesis_epoch,
             quorum_membership: quorum_membership.clone(),
             da_membership: da_membership.clone(),
             vid_disperse,
@@ -237,12 +245,16 @@ impl TestView {
             &metadata,
         );
 
-        let payload_commitment =
-            da_payload_commitment::<TestTypes>(quorum_membership, transactions.clone());
+        let payload_commitment = da_payload_commitment::<TestTypes>(
+            quorum_membership,
+            transactions.clone(),
+            self.epoch_number,
+        );
 
         let (vid_disperse, vid_proposal) = build_vid_proposal(
             quorum_membership,
             next_view,
+            self.epoch_number,
             transactions.clone(),
             &private_key,
         );
@@ -251,6 +263,7 @@ impl TestView {
             quorum_membership,
             da_membership,
             next_view,
+            self.epoch_number,
             transactions.clone(),
             &public_key,
             &private_key,
@@ -268,6 +281,7 @@ impl TestView {
             quorum_data,
             quorum_membership,
             old_view,
+            self.epoch_number,
             &old_public_key,
             &old_private_key,
             &self.upgrade_lock,
@@ -285,6 +299,7 @@ impl TestView {
                 data.clone(),
                 quorum_membership,
                 next_view,
+                self.epoch_number,
                 &public_key,
                 &private_key,
                 &self.upgrade_lock,
@@ -307,6 +322,7 @@ impl TestView {
                 data.clone(),
                 quorum_membership,
                 next_view,
+                self.epoch_number,
                 &public_key,
                 &private_key,
                 &self.upgrade_lock,
@@ -329,6 +345,7 @@ impl TestView {
                 data.clone(),
                 quorum_membership,
                 next_view,
+                self.epoch_number,
                 &public_key,
                 &private_key,
                 &self.upgrade_lock,
@@ -406,6 +423,7 @@ impl TestView {
             quorum_proposal,
             leaf,
             view_number: next_view,
+            epoch_number: self.epoch_number,
             quorum_membership: quorum_membership.clone(),
             da_membership: self.da_membership.clone(),
             vid_disperse,
diff --git a/crates/testing/tests/tests_1/da_task.rs b/crates/testing/tests/tests_1/da_task.rs
index b39f59ff32..1f78de5467 100644
--- a/crates/testing/tests/tests_1/da_task.rs
+++ b/crates/testing/tests/tests_1/da_task.rs
@@ -21,6 +21,7 @@ use hotshot_testing::{
     serial,
     view_generator::TestViewGenerator,
 };
+use hotshot_types::data::EpochNumber;
 use hotshot_types::{
     data::{null_block, PackedBundle, ViewNumber},
     simple_vote::DaData,
@@ -50,7 +51,11 @@ async fn test_da_task() {
     let encoded_transactions = Arc::from(TestTransaction::encode(&transactions));
     let (payload_commit, precompute) = precompute_vid_commitment(
         &encoded_transactions,
-        handle.hotshot.memberships.quorum_membership.total_nodes(),
+        handle
+            .hotshot
+            .memberships
+            .quorum_membership
+            .total_nodes(EpochNumber::new(0)),
     );
 
     let mut generator = TestViewGenerator::generate(quorum_membership.clone(), da_membership);
@@ -96,7 +101,7 @@ async fn test_da_task() {
                 },
                 ViewNumber::new(2),
                 vec1::vec1![null_block::builder_fee::<TestTypes, TestVersions>(
-                    quorum_membership.total_nodes(),
+                    quorum_membership.total_nodes(EpochNumber::new(0)),
                     <TestVersions as Versions>::Base::VERSION
                 )
                 .unwrap()],
@@ -147,7 +152,11 @@ async fn test_da_task_storage_failure() {
     let encoded_transactions = Arc::from(TestTransaction::encode(&transactions));
     let (payload_commit, precompute) = precompute_vid_commitment(
         &encoded_transactions,
-        handle.hotshot.memberships.quorum_membership.total_nodes(),
+        handle
+            .hotshot
+            .memberships
+            .quorum_membership
+            .total_nodes(EpochNumber::new(0)),
     );
 
     let mut generator = TestViewGenerator::generate(quorum_membership.clone(), da_membership);
@@ -193,7 +202,7 @@ async fn test_da_task_storage_failure() {
                 },
                 ViewNumber::new(2),
                 vec1::vec1![null_block::builder_fee::<TestTypes, TestVersions>(
-                    quorum_membership.total_nodes(),
+                    quorum_membership.total_nodes(EpochNumber::new(0)),
                     <TestVersions as Versions>::Base::VERSION
                 )
                 .unwrap()],
diff --git a/crates/testing/tests/tests_1/network_task.rs b/crates/testing/tests/tests_1/network_task.rs
index 272d132ae3..6a583c058f 100644
--- a/crates/testing/tests/tests_1/network_task.rs
+++ b/crates/testing/tests/tests_1/network_task.rs
@@ -17,6 +17,7 @@ use hotshot_testing::{
     helpers::build_system_handle, test_builder::TestDescription,
     test_task::add_network_message_test_task, view_generator::TestViewGenerator,
 };
+use hotshot_types::data::EpochNumber;
 use hotshot_types::{
     data::ViewNumber,
     message::UpgradeLock,
@@ -25,6 +26,7 @@ use hotshot_types::{
         node_implementation::{ConsensusTime, NodeType},
     },
 };
+
 // Test that the event task sends a message, and the message task receives it
 // and emits the proper event
 #[cfg(test)]
@@ -62,6 +64,7 @@ async fn test_network_task() {
         NetworkEventTaskState {
             network: network.clone(),
             view: ViewNumber::new(0),
+            epoch: EpochNumber::new(0),
             quorum_membership: membership.clone(),
             da_membership: membership.clone(),
             upgrade_lock: upgrade_lock.clone(),
@@ -242,6 +245,7 @@ async fn test_network_storage_fail() {
         NetworkEventTaskState {
             network: network.clone(),
             view: ViewNumber::new(0),
+            epoch: EpochNumber::new(0),
             quorum_membership: membership.clone(),
             da_membership: membership.clone(),
             upgrade_lock: upgrade_lock.clone(),
diff --git a/crates/testing/tests/tests_1/quorum_proposal_task.rs b/crates/testing/tests/tests_1/quorum_proposal_task.rs
index 455f304114..5be8b11ba1 100644
--- a/crates/testing/tests/tests_1/quorum_proposal_task.rs
+++ b/crates/testing/tests/tests_1/quorum_proposal_task.rs
@@ -24,6 +24,7 @@ use hotshot_testing::{
     serial,
     view_generator::TestViewGenerator,
 };
+use hotshot_types::data::EpochNumber;
 use hotshot_types::{
     data::{null_block, Leaf, ViewChangeEvidence, ViewNumber},
     simple_vote::{TimeoutData, ViewSyncFinalizeData},
@@ -56,8 +57,11 @@ async fn test_quorum_proposal_task_quorum_proposal_view_1() {
     let quorum_membership = handle.hotshot.memberships.quorum_membership.clone();
     let da_membership = handle.hotshot.memberships.da_membership.clone();
 
-    let payload_commitment =
-        build_payload_commitment::<TestTypes>(&quorum_membership, ViewNumber::new(node_id));
+    let payload_commitment = build_payload_commitment::<TestTypes>(
+        &quorum_membership,
+        ViewNumber::new(node_id),
+        EpochNumber::new(1),
+    );
 
     let mut generator = TestViewGenerator::generate(quorum_membership.clone(), da_membership);
 
@@ -89,7 +93,7 @@ async fn test_quorum_proposal_task_quorum_proposal_view_1() {
     let genesis_cert = proposals[0].data.justify_qc.clone();
     let builder_commitment = BuilderCommitment::from_raw_digest(sha2::Sha256::new().finalize());
     let builder_fee = null_block::builder_fee::<TestTypes, TestVersions>(
-        quorum_membership.total_nodes(),
+        quorum_membership.total_nodes(EpochNumber::new(1)),
         <TestVersions as Versions>::Base::VERSION,
     )
     .unwrap();
@@ -201,7 +205,7 @@ async fn test_quorum_proposal_task_quorum_proposal_view_gt_1() {
 
     let builder_commitment = BuilderCommitment::from_raw_digest(sha2::Sha256::new().finalize());
     let builder_fee = null_block::builder_fee::<TestTypes, TestVersions>(
-        quorum_membership.total_nodes(),
+        quorum_membership.total_nodes(EpochNumber::new(1)),
         <TestVersions as Versions>::Base::VERSION,
     )
     .unwrap();
@@ -210,7 +214,11 @@ async fn test_quorum_proposal_task_quorum_proposal_view_gt_1() {
         random![
             QcFormed(either::Left(genesis_cert.clone())),
             SendPayloadCommitmentAndMetadata(
-                build_payload_commitment::<TestTypes>(&quorum_membership, ViewNumber::new(1)),
+                build_payload_commitment::<TestTypes>(
+                    &quorum_membership,
+                    ViewNumber::new(1),
+                    EpochNumber::new(1)
+                ),
                 builder_commitment.clone(),
                 TestMetadata {
                     num_transactions: 0
@@ -229,7 +237,11 @@ async fn test_quorum_proposal_task_quorum_proposal_view_gt_1() {
             QuorumProposalPreliminarilyValidated(proposals[0].clone()),
             QcFormed(either::Left(proposals[1].data.justify_qc.clone())),
             SendPayloadCommitmentAndMetadata(
-                build_payload_commitment::<TestTypes>(&quorum_membership, ViewNumber::new(2)),
+                build_payload_commitment::<TestTypes>(
+                    &quorum_membership,
+                    ViewNumber::new(2),
+                    EpochNumber::new(1)
+                ),
                 builder_commitment.clone(),
                 proposals[0].data.block_header.metadata,
                 ViewNumber::new(2),
@@ -246,7 +258,11 @@ async fn test_quorum_proposal_task_quorum_proposal_view_gt_1() {
             QuorumProposalPreliminarilyValidated(proposals[1].clone()),
             QcFormed(either::Left(proposals[2].data.justify_qc.clone())),
             SendPayloadCommitmentAndMetadata(
-                build_payload_commitment::<TestTypes>(&quorum_membership, ViewNumber::new(3)),
+                build_payload_commitment::<TestTypes>(
+                    &quorum_membership,
+                    ViewNumber::new(3),
+                    EpochNumber::new(1)
+                ),
                 builder_commitment.clone(),
                 proposals[1].data.block_header.metadata,
                 ViewNumber::new(3),
@@ -263,7 +279,11 @@ async fn test_quorum_proposal_task_quorum_proposal_view_gt_1() {
             QuorumProposalPreliminarilyValidated(proposals[2].clone()),
             QcFormed(either::Left(proposals[3].data.justify_qc.clone())),
             SendPayloadCommitmentAndMetadata(
-                build_payload_commitment::<TestTypes>(&quorum_membership, ViewNumber::new(4)),
+                build_payload_commitment::<TestTypes>(
+                    &quorum_membership,
+                    ViewNumber::new(4),
+                    EpochNumber::new(1)
+                ),
                 builder_commitment.clone(),
                 proposals[2].data.block_header.metadata,
                 ViewNumber::new(4),
@@ -280,7 +300,11 @@ async fn test_quorum_proposal_task_quorum_proposal_view_gt_1() {
             QuorumProposalPreliminarilyValidated(proposals[3].clone()),
             QcFormed(either::Left(proposals[4].data.justify_qc.clone())),
             SendPayloadCommitmentAndMetadata(
-                build_payload_commitment::<TestTypes>(&quorum_membership, ViewNumber::new(5)),
+                build_payload_commitment::<TestTypes>(
+                    &quorum_membership,
+                    ViewNumber::new(5),
+                    EpochNumber::new(1)
+                ),
                 builder_commitment,
                 proposals[3].data.block_header.metadata,
                 ViewNumber::new(5),
@@ -347,8 +371,11 @@ async fn test_quorum_proposal_task_qc_timeout() {
     let quorum_membership = handle.hotshot.memberships.quorum_membership.clone();
     let da_membership = handle.hotshot.memberships.da_membership.clone();
 
-    let payload_commitment =
-        build_payload_commitment::<TestTypes>(&quorum_membership, ViewNumber::new(node_id));
+    let payload_commitment = build_payload_commitment::<TestTypes>(
+        &quorum_membership,
+        ViewNumber::new(node_id),
+        EpochNumber::new(1),
+    );
     let builder_commitment = BuilderCommitment::from_raw_digest(sha2::Sha256::new().finalize());
 
     let mut generator = TestViewGenerator::generate(quorum_membership.clone(), da_membership);
@@ -393,7 +420,7 @@ async fn test_quorum_proposal_task_qc_timeout() {
             },
             ViewNumber::new(3),
             vec1![null_block::builder_fee::<TestTypes, TestVersions>(
-                quorum_membership.total_nodes(),
+                quorum_membership.total_nodes(EpochNumber::new(1)),
                 <TestVersions as Versions>::Base::VERSION
             )
             .unwrap()],
@@ -437,8 +464,11 @@ async fn test_quorum_proposal_task_view_sync() {
     let quorum_membership = handle.hotshot.memberships.quorum_membership.clone();
     let da_membership = handle.hotshot.memberships.da_membership.clone();
 
-    let payload_commitment =
-        build_payload_commitment::<TestTypes>(&quorum_membership, ViewNumber::new(node_id));
+    let payload_commitment = build_payload_commitment::<TestTypes>(
+        &quorum_membership,
+        ViewNumber::new(node_id),
+        EpochNumber::new(1),
+    );
     let builder_commitment = BuilderCommitment::from_raw_digest(sha2::Sha256::new().finalize());
 
     let mut generator = TestViewGenerator::generate(quorum_membership.clone(), da_membership);
@@ -485,7 +515,7 @@ async fn test_quorum_proposal_task_view_sync() {
             },
             ViewNumber::new(2),
             vec1![null_block::builder_fee::<TestTypes, TestVersions>(
-                quorum_membership.total_nodes(),
+                quorum_membership.total_nodes(EpochNumber::new(1)),
                 <TestVersions as Versions>::Base::VERSION
             )
             .unwrap()],
@@ -562,7 +592,7 @@ async fn test_quorum_proposal_task_liveness_check() {
 
     let builder_commitment = BuilderCommitment::from_raw_digest(sha2::Sha256::new().finalize());
     let builder_fee = null_block::builder_fee::<TestTypes, TestVersions>(
-        quorum_membership.total_nodes(),
+        quorum_membership.total_nodes(EpochNumber::new(1)),
         <TestVersions as Versions>::Base::VERSION,
     )
     .unwrap();
@@ -580,7 +610,11 @@ async fn test_quorum_proposal_task_liveness_check() {
         random![
             QcFormed(either::Left(genesis_cert.clone())),
             SendPayloadCommitmentAndMetadata(
-                build_payload_commitment::<TestTypes>(&quorum_membership, ViewNumber::new(1)),
+                build_payload_commitment::<TestTypes>(
+                    &quorum_membership,
+                    ViewNumber::new(1),
+                    EpochNumber::new(1)
+                ),
                 builder_commitment.clone(),
                 TestMetadata {
                     num_transactions: 0
@@ -599,7 +633,11 @@ async fn test_quorum_proposal_task_liveness_check() {
             QuorumProposalPreliminarilyValidated(proposals[0].clone()),
             QcFormed(either::Left(proposals[1].data.justify_qc.clone())),
             SendPayloadCommitmentAndMetadata(
-                build_payload_commitment::<TestTypes>(&quorum_membership, ViewNumber::new(2)),
+                build_payload_commitment::<TestTypes>(
+                    &quorum_membership,
+                    ViewNumber::new(2),
+                    EpochNumber::new(1)
+                ),
                 builder_commitment.clone(),
                 proposals[0].data.block_header.metadata,
                 ViewNumber::new(2),
@@ -616,7 +654,11 @@ async fn test_quorum_proposal_task_liveness_check() {
             QuorumProposalPreliminarilyValidated(proposals[1].clone()),
             QcFormed(either::Left(proposals[2].data.justify_qc.clone())),
             SendPayloadCommitmentAndMetadata(
-                build_payload_commitment::<TestTypes>(&quorum_membership, ViewNumber::new(3)),
+                build_payload_commitment::<TestTypes>(
+                    &quorum_membership,
+                    ViewNumber::new(3),
+                    EpochNumber::new(1)
+                ),
                 builder_commitment.clone(),
                 proposals[1].data.block_header.metadata,
                 ViewNumber::new(3),
@@ -633,7 +675,11 @@ async fn test_quorum_proposal_task_liveness_check() {
             QuorumProposalPreliminarilyValidated(proposals[2].clone()),
             QcFormed(either::Left(proposals[3].data.justify_qc.clone())),
             SendPayloadCommitmentAndMetadata(
-                build_payload_commitment::<TestTypes>(&quorum_membership, ViewNumber::new(4)),
+                build_payload_commitment::<TestTypes>(
+                    &quorum_membership,
+                    ViewNumber::new(4),
+                    EpochNumber::new(1)
+                ),
                 builder_commitment.clone(),
                 proposals[2].data.block_header.metadata,
                 ViewNumber::new(4),
@@ -650,7 +696,11 @@ async fn test_quorum_proposal_task_liveness_check() {
             QuorumProposalPreliminarilyValidated(proposals[3].clone()),
             QcFormed(either::Left(proposals[4].data.justify_qc.clone())),
             SendPayloadCommitmentAndMetadata(
-                build_payload_commitment::<TestTypes>(&quorum_membership, ViewNumber::new(5)),
+                build_payload_commitment::<TestTypes>(
+                    &quorum_membership,
+                    ViewNumber::new(5),
+                    EpochNumber::new(1)
+                ),
                 builder_commitment,
                 proposals[3].data.block_header.metadata,
                 ViewNumber::new(5),
diff --git a/crates/testing/tests/tests_1/transaction_task.rs b/crates/testing/tests/tests_1/transaction_task.rs
index d73cd48ea7..b8c6a194b9 100644
--- a/crates/testing/tests/tests_1/transaction_task.rs
+++ b/crates/testing/tests/tests_1/transaction_task.rs
@@ -7,6 +7,7 @@ use hotshot_task_impls::{
     events::HotShotEvent, harness::run_harness, transactions::TransactionTaskState,
 };
 use hotshot_testing::helpers::build_system_handle;
+use hotshot_types::data::EpochNumber;
 use hotshot_types::{
     data::{null_block, PackedBundle, ViewNumber},
     traits::{
@@ -39,7 +40,8 @@ async fn test_transaction_task_leader_two_views_in_a_row() {
     input.push(HotShotEvent::Shutdown);
     let quorum_membership = handle.hotshot.memberships.quorum_membership.clone();
 
-    let (_, precompute_data) = precompute_vid_commitment(&[], quorum_membership.total_nodes());
+    let (_, precompute_data) =
+        precompute_vid_commitment(&[], quorum_membership.total_nodes(EpochNumber::new(0)));
 
     // current view
     let mut exp_packed_bundle = PackedBundle::new(
@@ -50,7 +52,7 @@ async fn test_transaction_task_leader_two_views_in_a_row() {
         current_view,
         vec1::vec1![
             null_block::builder_fee::<TestConsecutiveLeaderTypes, TestVersions>(
-                quorum_membership.total_nodes(),
+                quorum_membership.total_nodes(EpochNumber::new(0)),
                 <TestVersions as Versions>::Base::VERSION
             )
             .unwrap()
diff --git a/crates/testing/tests/tests_1/upgrade_task_with_proposal.rs b/crates/testing/tests/tests_1/upgrade_task_with_proposal.rs
index 5bf95997c0..f0493fb5e6 100644
--- a/crates/testing/tests/tests_1/upgrade_task_with_proposal.rs
+++ b/crates/testing/tests/tests_1/upgrade_task_with_proposal.rs
@@ -29,6 +29,7 @@ use hotshot_testing::{
     serial,
     view_generator::TestViewGenerator,
 };
+use hotshot_types::data::EpochNumber;
 use hotshot_types::{
     data::{null_block, Leaf, ViewNumber},
     simple_vote::UpgradeProposalData,
@@ -145,7 +146,7 @@ async fn test_upgrade_task_with_proposal() {
     let genesis_leaf = Leaf::genesis(&validated_state, &*handle.hotshot.instance_state()).await;
     let builder_commitment = BuilderCommitment::from_raw_digest(sha2::Sha256::new().finalize());
     let builder_fee = null_block::builder_fee::<TestTypes, TestVersions>(
-        quorum_membership.total_nodes(),
+        quorum_membership.total_nodes(EpochNumber::new(1)),
         <TestVersions as Versions>::Base::VERSION,
     )
     .unwrap();
@@ -171,7 +172,11 @@ async fn test_upgrade_task_with_proposal() {
         random![
             QcFormed(either::Left(genesis_cert.clone())),
             SendPayloadCommitmentAndMetadata(
-                build_payload_commitment::<TestTypes>(&quorum_membership, ViewNumber::new(1)),
+                build_payload_commitment::<TestTypes>(
+                    &quorum_membership,
+                    ViewNumber::new(1),
+                    EpochNumber::new(1)
+                ),
                 builder_commitment.clone(),
                 TestMetadata {
                     num_transactions: 0
@@ -190,7 +195,11 @@ async fn test_upgrade_task_with_proposal() {
             QuorumProposalPreliminarilyValidated(proposals[0].clone()),
             QcFormed(either::Left(proposals[1].data.justify_qc.clone())),
             SendPayloadCommitmentAndMetadata(
-                build_payload_commitment::<TestTypes>(&quorum_membership, ViewNumber::new(2)),
+                build_payload_commitment::<TestTypes>(
+                    &quorum_membership,
+                    ViewNumber::new(2),
+                    EpochNumber::new(1)
+                ),
                 builder_commitment.clone(),
                 proposals[0].data.block_header.metadata,
                 ViewNumber::new(2),
@@ -208,7 +217,11 @@ async fn test_upgrade_task_with_proposal() {
             QuorumProposalPreliminarilyValidated(proposals[1].clone()),
             QcFormed(either::Left(proposals[2].data.justify_qc.clone())),
             SendPayloadCommitmentAndMetadata(
-                build_payload_commitment::<TestTypes>(&quorum_membership, ViewNumber::new(3)),
+                build_payload_commitment::<TestTypes>(
+                    &quorum_membership,
+                    ViewNumber::new(3),
+                    EpochNumber::new(1)
+                ),
                 builder_commitment.clone(),
                 proposals[1].data.block_header.metadata,
                 ViewNumber::new(3),
diff --git a/crates/testing/tests/tests_1/vid_task.rs b/crates/testing/tests/tests_1/vid_task.rs
index 17922d42cb..714a12a3b5 100644
--- a/crates/testing/tests/tests_1/vid_task.rs
+++ b/crates/testing/tests/tests_1/vid_task.rs
@@ -20,6 +20,7 @@ use hotshot_testing::{
     script::{Expectations, InputOrder, TaskScript},
     serial,
 };
+use hotshot_types::data::EpochNumber;
 use hotshot_types::{
     data::{null_block, DaProposal, PackedBundle, VidDisperse, ViewNumber},
     traits::{
@@ -50,7 +51,11 @@ async fn test_vid_task() {
     // quorum membership for VID share distribution
     let quorum_membership = handle.hotshot.memberships.quorum_membership.clone();
 
-    let mut vid = vid_scheme_from_view_number::<TestTypes>(&quorum_membership, ViewNumber::new(0));
+    let mut vid = vid_scheme_from_view_number::<TestTypes>(
+        &quorum_membership,
+        ViewNumber::new(0),
+        EpochNumber::new(0),
+    );
     let transactions = vec![TestTransaction::new(vec![0])];
 
     let (payload, metadata) = <TestBlockPayload as BlockPayload<TestTypes>>::from_transactions(
@@ -85,8 +90,12 @@ async fn test_vid_task() {
         _pd: PhantomData,
     };
 
-    let vid_disperse =
-        VidDisperse::from_membership(message.data.view_number, vid_disperse, &quorum_membership);
+    let vid_disperse = VidDisperse::from_membership(
+        message.data.view_number,
+        vid_disperse,
+        &quorum_membership,
+        EpochNumber::new(0),
+    );
 
     let vid_proposal = Proposal {
         data: vid_disperse.clone(),
@@ -104,7 +113,7 @@ async fn test_vid_task() {
                 },
                 ViewNumber::new(2),
                 vec1::vec1![null_block::builder_fee::<TestTypes, TestVersions>(
-                    quorum_membership.total_nodes(),
+                    quorum_membership.total_nodes(EpochNumber::new(0)),
                     <TestVersions as Versions>::Base::VERSION
                 )
                 .unwrap()],
@@ -125,7 +134,7 @@ async fn test_vid_task() {
                 },
                 ViewNumber::new(2),
                 vec1![null_block::builder_fee::<TestTypes, TestVersions>(
-                    quorum_membership.total_nodes(),
+                    quorum_membership.total_nodes(EpochNumber::new(0)),
                     <TestVersions as Versions>::Base::VERSION
                 )
                 .unwrap()],
diff --git a/crates/testing/tests/tests_1/view_sync_task.rs b/crates/testing/tests/tests_1/view_sync_task.rs
index c0c4913981..5b2a9bf2d3 100644
--- a/crates/testing/tests/tests_1/view_sync_task.rs
+++ b/crates/testing/tests/tests_1/view_sync_task.rs
@@ -29,11 +29,11 @@ async fn test_view_sync_task() {
 
     let vote_data = ViewSyncPreCommitData {
         relay: 0,
-        round: <TestTypes as hotshot_types::traits::node_implementation::NodeType>::Time::new(4),
+        round: <TestTypes as hotshot_types::traits::node_implementation::NodeType>::View::new(4),
     };
     let vote = hotshot_types::simple_vote::ViewSyncPreCommitVote::<TestTypes>::create_signed_vote(
         vote_data,
-        <TestTypes as hotshot_types::traits::node_implementation::NodeType>::Time::new(4),
+        <TestTypes as hotshot_types::traits::node_implementation::NodeType>::View::new(4),
         hotshot_types::traits::consensus_api::ConsensusApi::public_key(&handle),
         hotshot_types::traits::consensus_api::ConsensusApi::private_key(&handle),
         &handle.hotshot.upgrade_lock,
diff --git a/crates/testing/tests/tests_1/vote_dependency_handle.rs b/crates/testing/tests/tests_1/vote_dependency_handle.rs
index 48fcffe5e7..6fe2979420 100644
--- a/crates/testing/tests/tests_1/vote_dependency_handle.rs
+++ b/crates/testing/tests/tests_1/vote_dependency_handle.rs
@@ -11,6 +11,7 @@ use hotshot_testing::{
     predicates::{event::*, Predicate, PredicateResult},
     view_generator::TestViewGenerator,
 };
+use hotshot_types::data::EpochNumber;
 use hotshot_types::{
     consensus::OuterConsensus,
     data::ViewNumber,
@@ -96,6 +97,7 @@ async fn test_vote_dependency_handle() {
                 quorum_membership: handle.hotshot.memberships.quorum_membership.clone().into(),
                 storage: Arc::clone(&handle.storage()),
                 view_number,
+                epoch_number: EpochNumber::new(1),
                 sender: event_sender.clone(),
                 receiver: event_receiver.clone(),
                 upgrade_lock: handle.hotshot.upgrade_lock.clone(),
diff --git a/crates/testing/tests/tests_3/byzantine_tests.rs b/crates/testing/tests/tests_3/byzantine_tests.rs
index 4687d3ff66..e5ac199aaf 100644
--- a/crates/testing/tests/tests_3/byzantine_tests.rs
+++ b/crates/testing/tests/tests_3/byzantine_tests.rs
@@ -21,7 +21,7 @@ use hotshot_testing::{
     test_builder::{Behaviour, TestDescription},
 };
 use hotshot_types::{
-    data::ViewNumber,
+    data::{EpochNumber, ViewNumber},
     message::{GeneralConsensusMessage, MessageKind, SequencingMessage},
     traits::{
         election::Membership,
@@ -176,7 +176,7 @@ cross_tests!(
                 view_increment: nodes_count as u64,
                 modifier: Arc::new(move |_pk, message_kind, transmit_type: &mut TransmitType<TestTypes>, membership: &<TestTypes as NodeType>::Membership| {
                     if let MessageKind::Consensus(SequencingMessage::General(GeneralConsensusMessage::Vote(vote))) = message_kind {
-                        *transmit_type = TransmitType::Direct(membership.leader(vote.view_number() + 1 - nodes_count as u64));
+                        *transmit_type = TransmitType::Direct(membership.leader(vote.view_number() + 1 - nodes_count as u64, EpochNumber::new(0)));
                     } else {
                         {}
                     }
diff --git a/crates/testing/tests/tests_3/memory_network.rs b/crates/testing/tests/tests_3/memory_network.rs
index 38b2da02e1..3050cd7d32 100644
--- a/crates/testing/tests/tests_3/memory_network.rs
+++ b/crates/testing/tests/tests_3/memory_network.rs
@@ -23,6 +23,7 @@ use hotshot_example_types::{
     state_types::{TestInstanceState, TestValidatedState},
     storage_types::TestStorage,
 };
+use hotshot_types::data::EpochNumber;
 use hotshot_types::{
     data::ViewNumber,
     message::{DataMessage, Message, MessageKind, UpgradeLock},
@@ -53,7 +54,8 @@ pub struct Test;
 
 impl NodeType for Test {
     type AuctionResult = TestAuctionResult;
-    type Time = ViewNumber;
+    type View = ViewNumber;
+    type Epoch = EpochNumber;
     type BlockHeader = TestBlockHeader;
     type BlockPayload = TestBlockPayload;
     type SignatureKey = BLSPubKey;
diff --git a/crates/types/src/consensus.rs b/crates/types/src/consensus.rs
index 759127fef5..a351a09b96 100644
--- a/crates/types/src/consensus.rs
+++ b/crates/types/src/consensus.rs
@@ -43,7 +43,7 @@ pub type CommitmentMap<T> = HashMap<Commitment<T>, T>;
 
 /// A type alias for `BTreeMap<T::Time, HashMap<T::SignatureKey, Proposal<T, VidDisperseShare<T>>>>`
 pub type VidShares<TYPES> = BTreeMap<
-    <TYPES as NodeType>::Time,
+    <TYPES as NodeType>::View,
     HashMap<<TYPES as NodeType>::SignatureKey, Proposal<TYPES, VidDisperseShare<TYPES>>>,
 >;
 
@@ -272,27 +272,30 @@ impl<T: ConsensusTime> HotShotActionViews<T> {
 #[derive(custom_debug::Debug, Clone)]
 pub struct Consensus<TYPES: NodeType> {
     /// The validated states that are currently loaded in memory.
-    validated_state_map: BTreeMap<TYPES::Time, View<TYPES>>,
+    validated_state_map: BTreeMap<TYPES::View, View<TYPES>>,
 
     /// All the VID shares we've received for current and future views.
     vid_shares: VidShares<TYPES>,
 
     /// All the DA certs we've received for current and future views.
     /// view -> DA cert
-    saved_da_certs: HashMap<TYPES::Time, DaCertificate<TYPES>>,
+    saved_da_certs: HashMap<TYPES::View, DaCertificate<TYPES>>,
 
     /// View number that is currently on.
-    cur_view: TYPES::Time,
+    cur_view: TYPES::View,
+
+    /// Epoch number that is currently on.
+    cur_epoch: TYPES::Epoch,
 
     /// Last proposals we sent out, None if we haven't proposed yet.
     /// Prevents duplicate proposals, and can be served to those trying to catchup
-    last_proposals: BTreeMap<TYPES::Time, Proposal<TYPES, QuorumProposal<TYPES>>>,
+    last_proposals: BTreeMap<TYPES::View, Proposal<TYPES, QuorumProposal<TYPES>>>,
 
     /// last view had a successful decide event
-    last_decided_view: TYPES::Time,
+    last_decided_view: TYPES::View,
 
     /// The `locked_qc` view number
-    locked_view: TYPES::Time,
+    locked_view: TYPES::View,
 
     /// Map of leaf hash -> leaf
     /// - contains undecided leaves
@@ -302,12 +305,12 @@ pub struct Consensus<TYPES: NodeType> {
     /// Bundle of views which we performed the most recent action
     /// visibible to the network.  Actions are votes and proposals
     /// for DA and Quorum
-    last_actions: HotShotActionViews<TYPES::Time>,
+    last_actions: HotShotActionViews<TYPES::View>,
 
     /// Saved payloads.
     ///
     /// Encoded transactions for every view if we got a payload for that view.
-    saved_payloads: BTreeMap<TYPES::Time, Arc<[u8]>>,
+    saved_payloads: BTreeMap<TYPES::View, Arc<[u8]>>,
 
     /// the highqc per spec
     high_qc: QuorumCertificate<TYPES>,
@@ -387,14 +390,15 @@ impl<TYPES: NodeType> Consensus<TYPES> {
     /// Constructor.
     #[allow(clippy::too_many_arguments)]
     pub fn new(
-        validated_state_map: BTreeMap<TYPES::Time, View<TYPES>>,
-        cur_view: TYPES::Time,
-        locked_view: TYPES::Time,
-        last_decided_view: TYPES::Time,
-        last_actioned_view: TYPES::Time,
-        last_proposals: BTreeMap<TYPES::Time, Proposal<TYPES, QuorumProposal<TYPES>>>,
+        validated_state_map: BTreeMap<TYPES::View, View<TYPES>>,
+        cur_view: TYPES::View,
+        cur_epoch: TYPES::Epoch,
+        locked_view: TYPES::View,
+        last_decided_view: TYPES::View,
+        last_actioned_view: TYPES::View,
+        last_proposals: BTreeMap<TYPES::View, Proposal<TYPES, QuorumProposal<TYPES>>>,
         saved_leaves: CommitmentMap<Leaf<TYPES>>,
-        saved_payloads: BTreeMap<TYPES::Time, Arc<[u8]>>,
+        saved_payloads: BTreeMap<TYPES::View, Arc<[u8]>>,
         high_qc: QuorumCertificate<TYPES>,
         metrics: Arc<ConsensusMetricsValue>,
     ) -> Self {
@@ -403,6 +407,7 @@ impl<TYPES: NodeType> Consensus<TYPES> {
             vid_shares: BTreeMap::new(),
             saved_da_certs: HashMap::new(),
             cur_view,
+            cur_epoch,
             last_decided_view,
             last_proposals,
             last_actions: HotShotActionViews::from_view(last_actioned_view),
@@ -415,17 +420,22 @@ impl<TYPES: NodeType> Consensus<TYPES> {
     }
 
     /// Get the current view.
-    pub fn cur_view(&self) -> TYPES::Time {
+    pub fn cur_view(&self) -> TYPES::View {
         self.cur_view
     }
 
+    /// Get the current epoch.
+    pub fn cur_epoch(&self) -> TYPES::Epoch {
+        self.cur_epoch
+    }
+
     /// Get the last decided view.
-    pub fn last_decided_view(&self) -> TYPES::Time {
+    pub fn last_decided_view(&self) -> TYPES::View {
         self.last_decided_view
     }
 
     /// Get the locked view.
-    pub fn locked_view(&self) -> TYPES::Time {
+    pub fn locked_view(&self) -> TYPES::View {
         self.locked_view
     }
 
@@ -435,7 +445,7 @@ impl<TYPES: NodeType> Consensus<TYPES> {
     }
 
     /// Get the validated state map.
-    pub fn validated_state_map(&self) -> &BTreeMap<TYPES::Time, View<TYPES>> {
+    pub fn validated_state_map(&self) -> &BTreeMap<TYPES::View, View<TYPES>> {
         &self.validated_state_map
     }
 
@@ -445,7 +455,7 @@ impl<TYPES: NodeType> Consensus<TYPES> {
     }
 
     /// Get the saved payloads.
-    pub fn saved_payloads(&self) -> &BTreeMap<TYPES::Time, Arc<[u8]>> {
+    pub fn saved_payloads(&self) -> &BTreeMap<TYPES::View, Arc<[u8]>> {
         &self.saved_payloads
     }
 
@@ -455,19 +465,19 @@ impl<TYPES: NodeType> Consensus<TYPES> {
     }
 
     /// Get the saved DA certs.
-    pub fn saved_da_certs(&self) -> &HashMap<TYPES::Time, DaCertificate<TYPES>> {
+    pub fn saved_da_certs(&self) -> &HashMap<TYPES::View, DaCertificate<TYPES>> {
         &self.saved_da_certs
     }
 
     /// Get the map of our recent proposals
-    pub fn last_proposals(&self) -> &BTreeMap<TYPES::Time, Proposal<TYPES, QuorumProposal<TYPES>>> {
+    pub fn last_proposals(&self) -> &BTreeMap<TYPES::View, Proposal<TYPES, QuorumProposal<TYPES>>> {
         &self.last_proposals
     }
 
     /// Update the current view.
     /// # Errors
     /// Can return an error when the new view_number is not higher than the existing view number.
-    pub fn update_view(&mut self, view_number: TYPES::Time) -> Result<()> {
+    pub fn update_view(&mut self, view_number: TYPES::View) -> Result<()> {
         ensure!(
             view_number > self.cur_view,
             "New view isn't newer than the current view."
@@ -476,10 +486,22 @@ impl<TYPES: NodeType> Consensus<TYPES> {
         Ok(())
     }
 
+    /// Update the current epoch.
+    /// # Errors
+    /// Can return an error when the new epoch_number is not higher than the existing epoch number.
+    pub fn update_epoch(&mut self, epoch_number: TYPES::Epoch) -> Result<()> {
+        ensure!(
+            epoch_number > self.cur_epoch,
+            "New epoch isn't newer than the current epoch."
+        );
+        self.cur_epoch = epoch_number;
+        Ok(())
+    }
+
     /// Update the last actioned view internally for votes and proposals
     ///
     /// Returns true if the action is for a newer view than the last action of that type
-    pub fn update_action(&mut self, action: HotShotAction, view: TYPES::Time) -> bool {
+    pub fn update_action(&mut self, action: HotShotAction, view: TYPES::View) -> bool {
         let old_view = match action {
             HotShotAction::Vote => &mut self.last_actions.voted,
             HotShotAction::Propose => &mut self.last_actions.proposed,
@@ -521,7 +543,7 @@ impl<TYPES: NodeType> Consensus<TYPES> {
                 > self
                     .last_proposals
                     .last_key_value()
-                    .map_or(TYPES::Time::genesis(), |(k, _)| { *k }),
+                    .map_or(TYPES::View::genesis(), |(k, _)| { *k }),
             "New view isn't newer than the previously proposed view."
         );
         self.last_proposals
@@ -533,7 +555,7 @@ impl<TYPES: NodeType> Consensus<TYPES> {
     ///
     /// # Errors
     /// Can return an error when the new view_number is not higher than the existing decided view number.
-    pub fn update_last_decided_view(&mut self, view_number: TYPES::Time) -> Result<()> {
+    pub fn update_last_decided_view(&mut self, view_number: TYPES::View) -> Result<()> {
         ensure!(
             view_number > self.last_decided_view,
             "New view isn't newer than the previously decided view."
@@ -546,7 +568,7 @@ impl<TYPES: NodeType> Consensus<TYPES> {
     ///
     /// # Errors
     /// Can return an error when the new view_number is not higher than the existing locked view number.
-    pub fn update_locked_view(&mut self, view_number: TYPES::Time) -> Result<()> {
+    pub fn update_locked_view(&mut self, view_number: TYPES::View) -> Result<()> {
         ensure!(
             view_number > self.locked_view,
             "New view isn't newer than the previously locked view."
@@ -562,7 +584,7 @@ impl<TYPES: NodeType> Consensus<TYPES> {
     /// with the same view number.
     pub fn update_validated_state_map(
         &mut self,
-        view_number: TYPES::Time,
+        view_number: TYPES::View,
         new_view: View<TYPES>,
     ) -> Result<()> {
         if let Some(existing_view) = self.validated_state_map().get(&view_number) {
@@ -607,7 +629,7 @@ impl<TYPES: NodeType> Consensus<TYPES> {
     /// Can return an error when there's an existing payload corresponding to the same view number.
     pub fn update_saved_payloads(
         &mut self,
-        view_number: TYPES::Time,
+        view_number: TYPES::View,
         encoded_transaction: Arc<[u8]>,
     ) -> Result<()> {
         ensure!(
@@ -635,7 +657,7 @@ impl<TYPES: NodeType> Consensus<TYPES> {
     /// Add a new entry to the vid_shares map.
     pub fn update_vid_shares(
         &mut self,
-        view_number: TYPES::Time,
+        view_number: TYPES::View,
         disperse: Proposal<TYPES, VidDisperseShare<TYPES>>,
     ) {
         self.vid_shares
@@ -645,7 +667,7 @@ impl<TYPES: NodeType> Consensus<TYPES> {
     }
 
     /// Add a new entry to the da_certs map.
-    pub fn update_saved_da_certs(&mut self, view_number: TYPES::Time, cert: DaCertificate<TYPES>) {
+    pub fn update_saved_da_certs(&mut self, view_number: TYPES::View, cert: DaCertificate<TYPES>) {
         self.saved_da_certs.insert(view_number, cert);
     }
 
@@ -654,8 +676,8 @@ impl<TYPES: NodeType> Consensus<TYPES> {
     /// If the leaf or its ancestors are not found in storage
     pub fn visit_leaf_ancestors<F>(
         &self,
-        start_from: TYPES::Time,
-        terminator: Terminator<TYPES::Time>,
+        start_from: TYPES::View,
+        terminator: Terminator<TYPES::View>,
         ok_when_finished: bool,
         mut f: F,
     ) -> Result<(), HotShotError<TYPES>>
@@ -714,7 +736,7 @@ impl<TYPES: NodeType> Consensus<TYPES> {
     /// `saved_payloads` and `validated_state_map` fields of `Consensus`.
     /// # Panics
     /// On inconsistent stored entries
-    pub fn collect_garbage(&mut self, old_anchor_view: TYPES::Time, new_anchor_view: TYPES::Time) {
+    pub fn collect_garbage(&mut self, old_anchor_view: TYPES::View, new_anchor_view: TYPES::View) {
         // state check
         let anchor_entry = self
             .validated_state_map
@@ -758,7 +780,7 @@ impl<TYPES: NodeType> Consensus<TYPES> {
 
     /// Gets the validated state with the given view number, if in the state map.
     #[must_use]
-    pub fn state(&self, view_number: TYPES::Time) -> Option<&Arc<TYPES::ValidatedState>> {
+    pub fn state(&self, view_number: TYPES::View) -> Option<&Arc<TYPES::ValidatedState>> {
         match self.validated_state_map.get(&view_number) {
             Some(view) => view.state(),
             None => None,
@@ -767,7 +789,7 @@ impl<TYPES: NodeType> Consensus<TYPES> {
 
     /// Gets the validated state and state delta with the given view number, if in the state map.
     #[must_use]
-    pub fn state_and_delta(&self, view_number: TYPES::Time) -> StateAndDelta<TYPES> {
+    pub fn state_and_delta(&self, view_number: TYPES::View) -> StateAndDelta<TYPES> {
         match self.validated_state_map.get(&view_number) {
             Some(view) => view.state_and_delta(),
             None => (None, None),
@@ -795,14 +817,16 @@ impl<TYPES: NodeType> Consensus<TYPES> {
     #[instrument(skip_all, target = "Consensus", fields(view = *view))]
     pub async fn calculate_and_update_vid(
         consensus: OuterConsensus<TYPES>,
-        view: <TYPES as NodeType>::Time,
+        view: <TYPES as NodeType>::View,
         membership: Arc<TYPES::Membership>,
         private_key: &<TYPES::SignatureKey as SignatureKey>::PrivateKey,
+        epoch: TYPES::Epoch,
     ) -> Option<()> {
         let consensus = consensus.upgradable_read().await;
         let txns = consensus.saved_payloads().get(&view)?;
         let vid =
-            VidDisperse::calculate_vid_disperse(Arc::clone(txns), &membership, view, None).await;
+            VidDisperse::calculate_vid_disperse(Arc::clone(txns), &membership, view, epoch, None)
+                .await;
         let shares = VidDisperseShare::from_vid_disperse(vid);
         let mut consensus = ConsensusUpgradableReadLockGuard::upgrade(consensus).await;
         for share in shares {
@@ -827,7 +851,7 @@ pub struct CommitmentAndMetadata<TYPES: NodeType> {
     /// Builder fee data
     pub fees: Vec1<BuilderFee<TYPES>>,
     /// View number this block is for
-    pub block_view: TYPES::Time,
+    pub block_view: TYPES::View,
     /// auction result that the block was produced from, if any
     pub auction_result: Option<TYPES::AuctionResult>,
 }
diff --git a/crates/types/src/data.rs b/crates/types/src/data.rs
index e70af8c294..3518f2e8bd 100644
--- a/crates/types/src/data.rs
+++ b/crates/types/src/data.rs
@@ -9,14 +9,6 @@
 //! This module provides types for representing consensus internal state, such as leaves,
 //! `HotShot`'s version of a block, and proposals, messages upon which to reach the consensus.
 
-use std::{
-    collections::BTreeMap,
-    fmt::{Debug, Display},
-    hash::Hash,
-    marker::PhantomData,
-    sync::Arc,
-};
-
 use anyhow::{ensure, Result};
 use ark_serialize::{CanonicalDeserialize, CanonicalSerialize};
 use async_lock::RwLock;
@@ -28,6 +20,13 @@ use derivative::Derivative;
 use jf_vid::{precomputable::Precomputable, VidDisperse as JfVidDisperse, VidScheme};
 use rand::Rng;
 use serde::{Deserialize, Serialize};
+use std::{
+    collections::BTreeMap,
+    fmt::{Debug, Display},
+    hash::Hash,
+    marker::PhantomData,
+    sync::Arc,
+};
 use thiserror::Error;
 #[cfg(async_executor_impl = "tokio")]
 use tokio::task::spawn_blocking;
@@ -56,6 +55,62 @@ use crate::{
     vote::{Certificate, HasViewNumber},
 };
 
+/// Implements `ConsensusTime`, `Display`, `Add`, `AddAssign`, `Deref` and `Sub`
+/// for the given thing wrapper type around u64.
+macro_rules! impl_u64_wrapper {
+    ($t:ty) => {
+        impl ConsensusTime for $t {
+            /// Create a genesis number (0)
+            fn genesis() -> Self {
+                Self(0)
+            }
+            /// Create a new number with the given value.
+            fn new(n: u64) -> Self {
+                Self(n)
+            }
+            /// Return the u64 format
+            fn u64(&self) -> u64 {
+                self.0
+            }
+        }
+
+        impl Display for $t {
+            fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+                write!(f, "{}", self.0)
+            }
+        }
+
+        impl std::ops::Add<u64> for $t {
+            type Output = $t;
+
+            fn add(self, rhs: u64) -> Self::Output {
+                Self(self.0 + rhs)
+            }
+        }
+
+        impl std::ops::AddAssign<u64> for $t {
+            fn add_assign(&mut self, rhs: u64) {
+                self.0 += rhs;
+            }
+        }
+
+        impl std::ops::Deref for $t {
+            type Target = u64;
+
+            fn deref(&self) -> &Self::Target {
+                &self.0
+            }
+        }
+
+        impl std::ops::Sub<u64> for $t {
+            type Output = $t;
+            fn sub(self, rhs: u64) -> Self::Output {
+                Self(self.0 - rhs)
+            }
+        }
+    };
+}
+
 /// Type-safe wrapper around `u64` so we know the thing we're talking about is a view number.
 #[derive(
     Copy,
@@ -73,27 +128,6 @@ use crate::{
 )]
 pub struct ViewNumber(u64);
 
-impl ConsensusTime for ViewNumber {
-    /// Create a genesis view number (0)
-    fn genesis() -> Self {
-        Self(0)
-    }
-    /// Create a new `ViewNumber` with the given value.
-    fn new(n: u64) -> Self {
-        Self(n)
-    }
-    /// Returen the u64 format
-    fn u64(&self) -> u64 {
-        self.0
-    }
-}
-
-impl Display for ViewNumber {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        write!(f, "{}", self.0)
-    }
-}
-
 impl Committable for ViewNumber {
     fn commit(&self) -> Commitment<Self> {
         let builder = RawCommitmentBuilder::new("View Number Commitment");
@@ -101,34 +135,33 @@ impl Committable for ViewNumber {
     }
 }
 
-impl std::ops::Add<u64> for ViewNumber {
-    type Output = ViewNumber;
-
-    fn add(self, rhs: u64) -> Self::Output {
-        Self(self.0 + rhs)
-    }
-}
-
-impl std::ops::AddAssign<u64> for ViewNumber {
-    fn add_assign(&mut self, rhs: u64) {
-        self.0 += rhs;
-    }
-}
+impl_u64_wrapper!(ViewNumber);
 
-impl std::ops::Deref for ViewNumber {
-    type Target = u64;
+/// Type-safe wrapper around `u64` so we know the thing we're talking about is a epoch number.
+#[derive(
+    Copy,
+    Clone,
+    Debug,
+    PartialEq,
+    Eq,
+    PartialOrd,
+    Ord,
+    Hash,
+    Serialize,
+    Deserialize,
+    CanonicalSerialize,
+    CanonicalDeserialize,
+)]
+pub struct EpochNumber(u64);
 
-    fn deref(&self) -> &Self::Target {
-        &self.0
+impl Committable for EpochNumber {
+    fn commit(&self) -> Commitment<Self> {
+        let builder = RawCommitmentBuilder::new("Epoch Number Commitment");
+        builder.u64(self.0).finalize()
     }
 }
 
-impl std::ops::Sub<u64> for ViewNumber {
-    type Output = ViewNumber;
-    fn sub(self, rhs: u64) -> Self::Output {
-        Self(self.0 - rhs)
-    }
-}
+impl_u64_wrapper!(EpochNumber);
 
 /// A proposal to start providing data availability for a block.
 #[derive(custom_debug::Debug, Serialize, Deserialize, Clone, Eq, PartialEq, Hash)]
@@ -139,7 +172,7 @@ pub struct DaProposal<TYPES: NodeType> {
     /// Metadata of the block to be applied.
     pub metadata: <TYPES::BlockPayload as BlockPayload<TYPES>>::Metadata,
     /// View this proposal applies to
-    pub view_number: TYPES::Time,
+    pub view_number: TYPES::View,
 }
 
 /// A proposal to upgrade the network
@@ -152,7 +185,7 @@ where
     /// The information about which version we are upgrading to.
     pub upgrade_proposal: UpgradeProposalData<TYPES>,
     /// View this proposal applies to
-    pub view_number: TYPES::Time,
+    pub view_number: TYPES::View,
 }
 
 /// VID dispersal data
@@ -163,7 +196,7 @@ where
 #[derive(Debug, Serialize, Deserialize, Clone, Eq, PartialEq, Hash)]
 pub struct VidDisperse<TYPES: NodeType> {
     /// The view number for which this VID data is intended
-    pub view_number: TYPES::Time,
+    pub view_number: TYPES::View,
     /// Block payload commitment
     pub payload_commitment: VidCommitment,
     /// A storage node's key and its corresponding VID share
@@ -173,16 +206,17 @@ pub struct VidDisperse<TYPES: NodeType> {
 }
 
 impl<TYPES: NodeType> VidDisperse<TYPES> {
-    /// Create VID dispersal from a specified membership
+    /// Create VID dispersal from a specified membership for a given epoch.
     /// Uses the specified function to calculate share dispersal
     /// Allows for more complex stake table functionality
     pub fn from_membership(
-        view_number: TYPES::Time,
+        view_number: TYPES::View,
         mut vid_disperse: JfVidDisperse<VidSchemeType>,
         membership: &TYPES::Membership,
+        epoch: TYPES::Epoch,
     ) -> Self {
         let shares = membership
-            .committee_members(view_number)
+            .committee_members(view_number, epoch)
             .iter()
             .map(|node| (node.clone(), vid_disperse.shares.remove(0)))
             .collect();
@@ -195,7 +229,7 @@ impl<TYPES: NodeType> VidDisperse<TYPES> {
         }
     }
 
-    /// Calculate the vid disperse information from the payload given a view and membership,
+    /// Calculate the vid disperse information from the payload given a view, epoch and membership,
     /// optionally using precompute data from builder
     ///
     /// # Panics
@@ -204,10 +238,11 @@ impl<TYPES: NodeType> VidDisperse<TYPES> {
     pub async fn calculate_vid_disperse(
         txns: Arc<[u8]>,
         membership: &Arc<TYPES::Membership>,
-        view: TYPES::Time,
+        view: TYPES::View,
+        epoch: TYPES::Epoch,
         precompute_data: Option<VidPrecomputeData>,
     ) -> Self {
-        let num_nodes = membership.total_nodes();
+        let num_nodes = membership.total_nodes(epoch);
 
         let vid_disperse = spawn_blocking(move || {
             precompute_data
@@ -222,7 +257,7 @@ impl<TYPES: NodeType> VidDisperse<TYPES> {
         // Unwrap here will just propagate any panic from the spawned task, it's not a new place we can panic.
         let vid_disperse = vid_disperse.unwrap();
 
-        Self::from_membership(view, vid_disperse, membership.as_ref())
+        Self::from_membership(view, vid_disperse, membership.as_ref(), epoch)
     }
 }
 
@@ -239,7 +274,7 @@ pub enum ViewChangeEvidence<TYPES: NodeType> {
 
 impl<TYPES: NodeType> ViewChangeEvidence<TYPES> {
     /// Check that the given ViewChangeEvidence is relevant to the current view.
-    pub fn is_valid_for_view(&self, view: &TYPES::Time) -> bool {
+    pub fn is_valid_for_view(&self, view: &TYPES::View) -> bool {
         match self {
             ViewChangeEvidence::Timeout(timeout_cert) => timeout_cert.data().view == *view - 1,
             ViewChangeEvidence::ViewSync(view_sync_cert) => view_sync_cert.view_number == *view,
@@ -251,7 +286,7 @@ impl<TYPES: NodeType> ViewChangeEvidence<TYPES> {
 /// VID share and associated metadata for a single node
 pub struct VidDisperseShare<TYPES: NodeType> {
     /// The view number for which this VID data is intended
-    pub view_number: TYPES::Time,
+    pub view_number: TYPES::View,
     /// Block payload commitment
     pub payload_commitment: VidCommitment,
     /// A storage node's key and its corresponding VID share
@@ -353,7 +388,7 @@ pub struct QuorumProposal<TYPES: NodeType> {
     pub block_header: TYPES::BlockHeader,
 
     /// CurView from leader when proposing leaf
-    pub view_number: TYPES::Time,
+    pub view_number: TYPES::View,
 
     /// Per spec, justification
     pub justify_qc: QuorumCertificate<TYPES>,
@@ -369,31 +404,31 @@ pub struct QuorumProposal<TYPES: NodeType> {
 }
 
 impl<TYPES: NodeType> HasViewNumber<TYPES> for DaProposal<TYPES> {
-    fn view_number(&self) -> TYPES::Time {
+    fn view_number(&self) -> TYPES::View {
         self.view_number
     }
 }
 
 impl<TYPES: NodeType> HasViewNumber<TYPES> for VidDisperse<TYPES> {
-    fn view_number(&self) -> TYPES::Time {
+    fn view_number(&self) -> TYPES::View {
         self.view_number
     }
 }
 
 impl<TYPES: NodeType> HasViewNumber<TYPES> for VidDisperseShare<TYPES> {
-    fn view_number(&self) -> TYPES::Time {
+    fn view_number(&self) -> TYPES::View {
         self.view_number
     }
 }
 
 impl<TYPES: NodeType> HasViewNumber<TYPES> for QuorumProposal<TYPES> {
-    fn view_number(&self) -> TYPES::Time {
+    fn view_number(&self) -> TYPES::View {
         self.view_number
     }
 }
 
 impl<TYPES: NodeType> HasViewNumber<TYPES> for UpgradeProposal<TYPES> {
-    fn view_number(&self) -> TYPES::Time {
+    fn view_number(&self) -> TYPES::View {
         self.view_number
     }
 }
@@ -430,7 +465,7 @@ pub trait TestableLeaf {
 #[serde(bound(deserialize = ""))]
 pub struct Leaf<TYPES: NodeType> {
     /// CurView from leader when proposing leaf
-    view_number: TYPES::Time,
+    view_number: TYPES::View,
 
     /// Per spec, justification
     justify_qc: QuorumCertificate<TYPES>,
@@ -503,7 +538,7 @@ impl<TYPES: NodeType> QuorumCertificate<TYPES> {
         // since this is genesis, we should never have a decided upgrade certificate.
         let upgrade_lock = UpgradeLock::<TYPES, V>::new();
 
-        let genesis_view = <TYPES::Time as ConsensusTime>::genesis();
+        let genesis_view = <TYPES::View as ConsensusTime>::genesis();
 
         let data = QuorumData {
             leaf_commit: Leaf::genesis(validated_state, instance_state)
@@ -563,13 +598,13 @@ impl<TYPES: NodeType> Leaf<TYPES> {
         let justify_qc = QuorumCertificate::new(
             null_quorum_data.clone(),
             null_quorum_data.commit(),
-            <TYPES::Time as ConsensusTime>::genesis(),
+            <TYPES::View as ConsensusTime>::genesis(),
             None,
             PhantomData,
         );
 
         Self {
-            view_number: TYPES::Time::genesis(),
+            view_number: TYPES::View::genesis(),
             justify_qc,
             parent_commitment: null_quorum_data.leaf_commit,
             upgrade_certificate: None,
@@ -579,7 +614,7 @@ impl<TYPES: NodeType> Leaf<TYPES> {
     }
 
     /// Time when this leaf was created.
-    pub fn view_number(&self) -> TYPES::Time {
+    pub fn view_number(&self) -> TYPES::View {
         self.view_number
     }
     /// Height of this leaf in the chain.
@@ -866,7 +901,7 @@ pub struct PackedBundle<TYPES: NodeType> {
     pub metadata: <TYPES::BlockPayload as BlockPayload<TYPES>>::Metadata,
 
     /// The view number that this block is associated with.
-    pub view_number: TYPES::Time,
+    pub view_number: TYPES::View,
 
     /// The sequencing fee for submitting bundles.
     pub sequencing_fees: Vec1<BuilderFee<TYPES>>,
@@ -883,7 +918,7 @@ impl<TYPES: NodeType> PackedBundle<TYPES> {
     pub fn new(
         encoded_transactions: Arc<[u8]>,
         metadata: <TYPES::BlockPayload as BlockPayload<TYPES>>::Metadata,
-        view_number: TYPES::Time,
+        view_number: TYPES::View,
         sequencing_fees: Vec1<BuilderFee<TYPES>>,
         vid_precompute: Option<VidPrecomputeData>,
         auction_result: Option<TYPES::AuctionResult>,
diff --git a/crates/types/src/error.rs b/crates/types/src/error.rs
index f76c46906f..80c1baae8d 100644
--- a/crates/types/src/error.rs
+++ b/crates/types/src/error.rs
@@ -41,7 +41,7 @@ pub enum HotShotError<TYPES: NodeType> {
     #[error("View {view_number} timed out: {state:?}")]
     ViewTimedOut {
         /// The view number that timed out
-        view_number: TYPES::Time,
+        view_number: TYPES::View,
         /// The state that the round was in when it timed out
         state: RoundTimedoutState,
     },
diff --git a/crates/types/src/event.rs b/crates/types/src/event.rs
index e71d0c8196..ca833c9f5d 100644
--- a/crates/types/src/event.rs
+++ b/crates/types/src/event.rs
@@ -25,7 +25,7 @@ use crate::{
 #[serde(bound(deserialize = "TYPES: NodeType"))]
 pub struct Event<TYPES: NodeType> {
     /// The view number that this event originates from
-    pub view_number: TYPES::Time,
+    pub view_number: TYPES::View,
     /// The underlying event
     pub event: EventType<TYPES>,
 }
@@ -128,17 +128,17 @@ pub enum EventType<TYPES: NodeType> {
     /// A replica task was canceled by a timeout interrupt
     ReplicaViewTimeout {
         /// The view that timed out
-        view_number: TYPES::Time,
+        view_number: TYPES::View,
     },
     /// The view has finished.  If values were decided on, a `Decide` event will also be emitted.
     ViewFinished {
         /// The view number that has just finished
-        view_number: TYPES::Time,
+        view_number: TYPES::View,
     },
     /// The view timed out
     ViewTimeout {
         /// The view that timed out
-        view_number: TYPES::Time,
+        view_number: TYPES::View,
     },
     /// New transactions were received from the network
     /// or submitted to the network by us
diff --git a/crates/types/src/hotshot_config_file.rs b/crates/types/src/hotshot_config_file.rs
index 37457b8d28..08b81af3e4 100644
--- a/crates/types/src/hotshot_config_file.rs
+++ b/crates/types/src/hotshot_config_file.rs
@@ -65,6 +65,8 @@ pub struct HotShotConfigFile<KEY: SignatureKey> {
     pub builder_urls: Vec1<Url>,
     /// Upgrade config
     pub upgrade: UpgradeConfig,
+    /// Number of blocks in an epoch, zero means there are no epochs
+    pub epoch_height: u64,
 }
 
 impl<KEY: SignatureKey> From<HotShotConfigFile<KEY>> for HotShotConfig<KEY> {
@@ -98,6 +100,7 @@ impl<KEY: SignatureKey> From<HotShotConfigFile<KEY>> for HotShotConfig<KEY> {
             stop_proposing_time: val.upgrade.stop_proposing_time,
             start_voting_time: val.upgrade.start_voting_time,
             stop_voting_time: val.upgrade.stop_voting_time,
+            epoch_height: val.epoch_height,
         }
     }
 }
@@ -147,6 +150,7 @@ impl<KEY: SignatureKey> HotShotConfigFile<KEY> {
             data_request_delay: Some(Duration::from_millis(REQUEST_DATA_DELAY)),
             builder_urls: default_builder_urls(),
             upgrade: UpgradeConfig::default(),
+            epoch_height: 0,
         }
     }
 }
diff --git a/crates/types/src/lib.rs b/crates/types/src/lib.rs
index 806667bf9b..897fef5c73 100644
--- a/crates/types/src/lib.rs
+++ b/crates/types/src/lib.rs
@@ -232,6 +232,8 @@ pub struct HotShotConfig<KEY: SignatureKey> {
     pub start_voting_time: u64,
     /// Unix time in seconds at which we stop voting on an upgrade. To prevent voting on an upgrade, set stop_voting_time <= start_voting_time.
     pub stop_voting_time: u64,
+    /// Number of blocks in an epoch, zero means there are no epochs
+    pub epoch_height: u64,
 }
 
 impl<KEY: SignatureKey> HotShotConfig<KEY> {
diff --git a/crates/types/src/message.rs b/crates/types/src/message.rs
index ab72986652..42ae087b9a 100644
--- a/crates/types/src/message.rs
+++ b/crates/types/src/message.rs
@@ -67,7 +67,7 @@ impl<TYPES: NodeType> fmt::Debug for Message<TYPES> {
 
 impl<TYPES: NodeType> HasViewNumber<TYPES> for Message<TYPES> {
     /// get the view number out of a message
-    fn view_number(&self) -> TYPES::Time {
+    fn view_number(&self) -> TYPES::View {
         self.kind.view_number()
     }
 }
@@ -147,16 +147,16 @@ impl<TYPES: NodeType> From<DataMessage<TYPES>> for MessageKind<TYPES> {
 }
 
 impl<TYPES: NodeType> ViewMessage<TYPES> for MessageKind<TYPES> {
-    fn view_number(&self) -> TYPES::Time {
+    fn view_number(&self) -> TYPES::View {
         match &self {
             MessageKind::Consensus(message) => message.view_number(),
             MessageKind::Data(DataMessage::SubmitTransaction(_, v)) => *v,
             MessageKind::Data(DataMessage::RequestData(msg)) => msg.view,
             MessageKind::Data(DataMessage::DataResponse(msg)) => match msg {
                 ResponseMessage::Found(m) => m.view_number(),
-                ResponseMessage::NotFound | ResponseMessage::Denied => TYPES::Time::new(1),
+                ResponseMessage::NotFound | ResponseMessage::Denied => TYPES::View::new(1),
             },
-            MessageKind::External(_) => TYPES::Time::new(1),
+            MessageKind::External(_) => TYPES::View::new(1),
         }
     }
 
@@ -248,7 +248,7 @@ pub enum SequencingMessage<TYPES: NodeType> {
 
 impl<TYPES: NodeType> SequencingMessage<TYPES> {
     /// Get the view number this message relates to
-    fn view_number(&self) -> TYPES::Time {
+    fn view_number(&self) -> TYPES::View {
         match &self {
             SequencingMessage::General(general_message) => {
                 match general_message {
@@ -342,7 +342,7 @@ pub enum DataMessage<TYPES: NodeType> {
     /// Contains a transaction to be submitted
     /// TODO rethink this when we start to send these messages
     /// we only need the view number for broadcast
-    SubmitTransaction(TYPES::Transaction, TYPES::Time),
+    SubmitTransaction(TYPES::Transaction, TYPES::View),
     /// A request for data
     RequestData(DataRequest<TYPES>),
     /// A response to a data request
@@ -373,10 +373,11 @@ where
     pub async fn validate_signature<V: Versions>(
         &self,
         quorum_membership: &TYPES::Membership,
+        epoch: TYPES::Epoch,
         upgrade_lock: &UpgradeLock<TYPES, V>,
     ) -> Result<()> {
         let view_number = self.data.view_number();
-        let view_leader_key = quorum_membership.leader(view_number);
+        let view_leader_key = quorum_membership.leader(view_number, epoch);
         let proposed_leaf = Leaf::from_quorum_proposal(&self.data);
 
         ensure!(
@@ -424,7 +425,7 @@ impl<TYPES: NodeType, V: Versions> UpgradeLock<TYPES, V> {
     ///
     /// # Errors
     /// Returns an error if we do not support the version required by the decided upgrade certificate.
-    pub async fn version(&self, view: TYPES::Time) -> Result<Version> {
+    pub async fn version(&self, view: TYPES::View) -> Result<Version> {
         let upgrade_certificate = self.decided_upgrade_certificate.read().await;
 
         let version = match *upgrade_certificate {
@@ -448,7 +449,7 @@ impl<TYPES: NodeType, V: Versions> UpgradeLock<TYPES, V> {
     /// Calculate the version applied in a view, based on the provided upgrade lock.
     ///
     /// This function does not fail, since it does not check that the version is supported.
-    pub async fn version_infallible(&self, view: TYPES::Time) -> Version {
+    pub async fn version_infallible(&self, view: TYPES::View) -> Version {
         let upgrade_certificate = self.decided_upgrade_certificate.read().await;
 
         match *upgrade_certificate {
diff --git a/crates/types/src/request_response.rs b/crates/types/src/request_response.rs
index d27cc27313..6829d19743 100644
--- a/crates/types/src/request_response.rs
+++ b/crates/types/src/request_response.rs
@@ -16,7 +16,7 @@ use crate::traits::{node_implementation::NodeType, signature_key::SignatureKey};
 /// A signed request for a proposal.
 pub struct ProposalRequestPayload<TYPES: NodeType> {
     /// The view number that we're requesting a proposal for.
-    pub view_number: TYPES::Time,
+    pub view_number: TYPES::View,
 
     /// Our public key. The ensures that the receipient can reply to
     /// us directly.
diff --git a/crates/types/src/simple_certificate.rs b/crates/types/src/simple_certificate.rs
index 6e9e7bbbfb..bbdc88eb05 100644
--- a/crates/types/src/simple_certificate.rs
+++ b/crates/types/src/simple_certificate.rs
@@ -78,7 +78,7 @@ pub struct SimpleCertificate<TYPES: NodeType, VOTEABLE: Voteable, THRESHOLD: Thr
     /// commitment of all the votes this cert should be signed over
     vote_commitment: Commitment<VOTEABLE>,
     /// Which view this QC relates to
-    pub view_number: TYPES::Time,
+    pub view_number: TYPES::View,
     /// assembled signature for certificate aggregation
     pub signatures: Option<<TYPES::SignatureKey as SignatureKey>::QcType>,
     /// phantom data for `THRESHOLD` and `TYPES`
@@ -92,7 +92,7 @@ impl<TYPES: NodeType, VOTEABLE: Voteable, THRESHOLD: Threshold<TYPES>>
     pub fn new(
         data: VOTEABLE,
         vote_commitment: Commitment<VOTEABLE>,
-        view_number: TYPES::Time,
+        view_number: TYPES::View,
         signatures: Option<<TYPES::SignatureKey as SignatureKey>::QcType>,
         pd: PhantomData<(TYPES, THRESHOLD)>,
     ) -> Self {
@@ -133,7 +133,7 @@ impl<TYPES: NodeType, VOTEABLE: Voteable + 'static, THRESHOLD: Threshold<TYPES>>
         vote_commitment: Commitment<VersionedVoteData<TYPES, VOTEABLE, V>>,
         data: Self::Voteable,
         sig: <TYPES::SignatureKey as SignatureKey>::QcType,
-        view: TYPES::Time,
+        view: TYPES::View,
     ) -> Self {
         let vote_commitment_bytes: [u8; 32] = vote_commitment.into();
 
@@ -148,13 +148,14 @@ impl<TYPES: NodeType, VOTEABLE: Voteable + 'static, THRESHOLD: Threshold<TYPES>>
     async fn is_valid_cert<MEMBERSHIP: Membership<TYPES>, V: Versions>(
         &self,
         membership: &MEMBERSHIP,
+        epoch: TYPES::Epoch,
         upgrade_lock: &UpgradeLock<TYPES, V>,
     ) -> bool {
-        if self.view_number == TYPES::Time::genesis() {
+        if self.view_number == TYPES::View::genesis() {
             return true;
         }
         let real_qc_pp = <TYPES::SignatureKey as SignatureKey>::public_parameter(
-            membership.stake_table(),
+            membership.stake_table(epoch),
             U256::from(Self::threshold(membership)),
         );
         let Ok(commit) = self.data_commitment(upgrade_lock).await else {
@@ -187,7 +188,7 @@ impl<TYPES: NodeType, VOTEABLE: Voteable + 'static, THRESHOLD: Threshold<TYPES>>
 impl<TYPES: NodeType, VOTEABLE: Voteable + 'static, THRESHOLD: Threshold<TYPES>>
     HasViewNumber<TYPES> for SimpleCertificate<TYPES, VOTEABLE, THRESHOLD>
 {
-    fn view_number(&self) -> TYPES::Time {
+    fn view_number(&self) -> TYPES::View {
         self.view_number
     }
 }
@@ -205,7 +206,7 @@ impl<TYPES: NodeType> UpgradeCertificate<TYPES> {
     /// Returns an error when the certificate is no longer relevant
     pub async fn is_relevant(
         &self,
-        view_number: TYPES::Time,
+        view_number: TYPES::View,
         decided_upgrade_certificate: Arc<RwLock<Option<Self>>>,
     ) -> Result<()> {
         let decided_upgrade_certificate_read = decided_upgrade_certificate.read().await;
@@ -226,11 +227,13 @@ impl<TYPES: NodeType> UpgradeCertificate<TYPES> {
     pub async fn validate<V: Versions>(
         upgrade_certificate: &Option<Self>,
         quorum_membership: &TYPES::Membership,
+        epoch: TYPES::Epoch,
         upgrade_lock: &UpgradeLock<TYPES, V>,
     ) -> Result<()> {
         if let Some(ref cert) = upgrade_certificate {
             ensure!(
-                cert.is_valid_cert(quorum_membership, upgrade_lock).await,
+                cert.is_valid_cert(quorum_membership, epoch, upgrade_lock)
+                    .await,
                 "Invalid upgrade certificate."
             );
             Ok(())
@@ -241,7 +244,7 @@ impl<TYPES: NodeType> UpgradeCertificate<TYPES> {
 
     /// Given an upgrade certificate and a view, tests whether the view is in the period
     /// where we are upgrading, which requires that we propose with null blocks.
-    pub fn upgrading_in(&self, view: TYPES::Time) -> bool {
+    pub fn upgrading_in(&self, view: TYPES::View) -> bool {
         view > self.data.old_version_last_view && view < self.data.new_version_first_view
     }
 }
diff --git a/crates/types/src/simple_vote.rs b/crates/types/src/simple_vote.rs
index 45e131f756..1c1fcba31b 100644
--- a/crates/types/src/simple_vote.rs
+++ b/crates/types/src/simple_vote.rs
@@ -41,7 +41,7 @@ pub struct DaData {
 /// Data used for a timeout vote.
 pub struct TimeoutData<TYPES: NodeType> {
     /// View the timeout is for
-    pub view: TYPES::Time,
+    pub view: TYPES::View,
 }
 #[derive(Serialize, Deserialize, Clone, Debug, PartialEq, Hash, Eq)]
 /// Data used for a VID vote.
@@ -55,7 +55,7 @@ pub struct ViewSyncPreCommitData<TYPES: NodeType> {
     /// The relay this vote is intended for
     pub relay: u64,
     /// The view number we are trying to sync on
-    pub round: TYPES::Time,
+    pub round: TYPES::View,
 }
 #[derive(Serialize, Deserialize, Clone, Debug, PartialEq, Hash, Eq)]
 /// Data used for a Commit vote.
@@ -63,7 +63,7 @@ pub struct ViewSyncCommitData<TYPES: NodeType> {
     /// The relay this vote is intended for
     pub relay: u64,
     /// The view number we are trying to sync on
-    pub round: TYPES::Time,
+    pub round: TYPES::View,
 }
 #[derive(Serialize, Deserialize, Clone, Debug, PartialEq, Hash, Eq)]
 /// Data used for a Finalize vote.
@@ -71,7 +71,7 @@ pub struct ViewSyncFinalizeData<TYPES: NodeType> {
     /// The relay this vote is intended for
     pub relay: u64,
     /// The view number we are trying to sync on
-    pub round: TYPES::Time,
+    pub round: TYPES::View,
 }
 #[derive(Serialize, Deserialize, Clone, Debug, PartialEq, Hash, Eq)]
 /// Data used for a Upgrade vote.
@@ -82,13 +82,13 @@ pub struct UpgradeProposalData<TYPES: NodeType + DeserializeOwned> {
     pub new_version: Version,
     /// The last view in which we are allowed to reach a decide on this upgrade.
     /// If it is not decided by that view, we discard it.
-    pub decide_by: TYPES::Time,
+    pub decide_by: TYPES::View,
     /// A unique identifier for the specific protocol being voted on.
     pub new_version_hash: Vec<u8>,
     /// The last block for which the old version will be in effect.
-    pub old_version_last_view: TYPES::Time,
+    pub old_version_last_view: TYPES::View,
     /// The first block for which the new version will be in effect.
-    pub new_version_first_view: TYPES::Time,
+    pub new_version_first_view: TYPES::View,
 }
 
 /// Marker trait for data or commitments that can be voted on.
@@ -123,11 +123,11 @@ pub struct SimpleVote<TYPES: NodeType, DATA: Voteable> {
     /// The leaf commitment being voted on.
     pub data: DATA,
     /// The view this vote was cast for
-    pub view_number: TYPES::Time,
+    pub view_number: TYPES::View,
 }
 
 impl<TYPES: NodeType, DATA: Voteable + 'static> HasViewNumber<TYPES> for SimpleVote<TYPES, DATA> {
-    fn view_number(&self) -> <TYPES as NodeType>::Time {
+    fn view_number(&self) -> <TYPES as NodeType>::View {
         self.view_number
     }
 }
@@ -158,7 +158,7 @@ impl<TYPES: NodeType, DATA: Voteable + 'static> SimpleVote<TYPES, DATA> {
     /// If we are unable to sign the data
     pub async fn create_signed_vote<V: Versions>(
         data: DATA,
-        view: TYPES::Time,
+        view: TYPES::View,
         pub_key: &TYPES::SignatureKey,
         private_key: &<TYPES::SignatureKey as SignatureKey>::PrivateKey,
         upgrade_lock: &UpgradeLock<TYPES, V>,
@@ -187,7 +187,7 @@ pub struct VersionedVoteData<TYPES: NodeType, DATA: Voteable, V: Versions> {
     data: DATA,
 
     /// view number
-    view: TYPES::Time,
+    view: TYPES::View,
 
     /// version applied to the view number
     version: Version,
@@ -204,7 +204,7 @@ impl<TYPES: NodeType, DATA: Voteable, V: Versions> VersionedVoteData<TYPES, DATA
     /// Returns an error if `upgrade_lock.version(view)` is unable to return a version we support
     pub async fn new(
         data: DATA,
-        view: TYPES::Time,
+        view: TYPES::View,
         upgrade_lock: &UpgradeLock<TYPES, V>,
     ) -> Result<Self> {
         let version = upgrade_lock.version(view).await?;
@@ -222,7 +222,7 @@ impl<TYPES: NodeType, DATA: Voteable, V: Versions> VersionedVoteData<TYPES, DATA
     /// This function cannot error, but may use an invalid version.
     pub async fn new_infallible(
         data: DATA,
-        view: TYPES::Time,
+        view: TYPES::View,
         upgrade_lock: &UpgradeLock<TYPES, V>,
     ) -> Self {
         let version = upgrade_lock.version_infallible(view).await;
@@ -303,7 +303,7 @@ impl<TYPES: NodeType> Committable for UpgradeProposalData<TYPES> {
 
 /// This implements commit for all the types which contain a view and relay public key.
 fn view_and_relay_commit<TYPES: NodeType, T: Committable>(
-    view: TYPES::Time,
+    view: TYPES::View,
     relay: u64,
     tag: &str,
 ) -> Commitment<T> {
diff --git a/crates/types/src/traits/auction_results_provider.rs b/crates/types/src/traits/auction_results_provider.rs
index 283ada9d68..7fcd8498e4 100644
--- a/crates/types/src/traits/auction_results_provider.rs
+++ b/crates/types/src/traits/auction_results_provider.rs
@@ -20,5 +20,5 @@ use super::node_implementation::NodeType;
 pub trait AuctionResultsProvider<TYPES: NodeType>: Send + Sync + Clone {
     /// Fetches the auction result for a view. Does not cache the result,
     /// subsequent calls will invoke additional wasted calls.
-    async fn fetch_auction_result(&self, view_number: TYPES::Time) -> Result<TYPES::AuctionResult>;
+    async fn fetch_auction_result(&self, view_number: TYPES::View) -> Result<TYPES::AuctionResult>;
 }
diff --git a/crates/types/src/traits/election.rs b/crates/types/src/traits/election.rs
index b03bf8a843..43d0ebf12f 100644
--- a/crates/types/src/traits/election.rs
+++ b/crates/types/src/traits/election.rs
@@ -23,33 +23,45 @@ pub trait Membership<TYPES: NodeType>:
         committee_topic: Topic,
     ) -> Self;
 
-    /// Get all participants in the committee (including their stake)
-    fn stake_table(&self) -> Vec<<TYPES::SignatureKey as SignatureKey>::StakeTableEntry>;
+    /// Get all participants in the committee (including their stake) for a specific epoch
+    fn stake_table(
+        &self,
+        epoch: TYPES::Epoch,
+    ) -> Vec<<TYPES::SignatureKey as SignatureKey>::StakeTableEntry>;
 
-    /// Get all participants in the committee for a specific view
-    fn committee_members(&self, view_number: TYPES::Time) -> BTreeSet<TYPES::SignatureKey>;
+    /// Get all participants in the committee for a specific view for a specific epoch
+    fn committee_members(
+        &self,
+        view_number: TYPES::View,
+        epoch: TYPES::Epoch,
+    ) -> BTreeSet<TYPES::SignatureKey>;
 
-    /// Get all leaders in the committee for a specific view
-    fn committee_leaders(&self, view_number: TYPES::Time) -> BTreeSet<TYPES::SignatureKey>;
+    /// Get all leaders in the committee for a specific view for a specific epoch
+    fn committee_leaders(
+        &self,
+        view_number: TYPES::View,
+        epoch: TYPES::Epoch,
+    ) -> BTreeSet<TYPES::SignatureKey>;
 
     /// Get the stake table entry for a public key, returns `None` if the
-    /// key is not in the table
+    /// key is not in the table for a specific epoch
     fn stake(
         &self,
         pub_key: &TYPES::SignatureKey,
+        epoch: TYPES::Epoch,
     ) -> Option<<TYPES::SignatureKey as SignatureKey>::StakeTableEntry>;
 
-    /// See if a node has stake in the committee
-    fn has_stake(&self, pub_key: &TYPES::SignatureKey) -> bool;
+    /// See if a node has stake in the committee in a specific epoch
+    fn has_stake(&self, pub_key: &TYPES::SignatureKey, epoch: TYPES::Epoch) -> bool;
 
-    /// The leader of the committee for view `view_number`.
-    fn leader(&self, view_number: TYPES::Time) -> TYPES::SignatureKey;
+    /// The leader of the committee for view `view_number` in an epoch `epoch`.
+    fn leader(&self, view_number: TYPES::View, epoch: TYPES::Epoch) -> TYPES::SignatureKey;
 
     /// Get the network topic for the committee
     fn committee_topic(&self) -> Topic;
 
-    /// Returns the number of total nodes in the committee
-    fn total_nodes(&self) -> usize;
+    /// Returns the number of total nodes in the committee in an epoch `epoch`
+    fn total_nodes(&self, epoch: TYPES::Epoch) -> usize;
 
     /// Returns the threshold for a specific `Membership` implementation
     fn success_threshold(&self) -> NonZeroU64;
diff --git a/crates/types/src/traits/network.rs b/crates/types/src/traits/network.rs
index 97851e6963..27fe0ec3c9 100644
--- a/crates/types/src/traits/network.rs
+++ b/crates/types/src/traits/network.rs
@@ -126,7 +126,7 @@ pub trait Id: Eq + PartialEq + Hash {}
 /// a message
 pub trait ViewMessage<TYPES: NodeType> {
     /// get the view out of the message
-    fn view_number(&self) -> TYPES::Time;
+    fn view_number(&self) -> TYPES::View;
     // TODO move out of this trait.
     /// get the purpose of the message
     fn purpose(&self) -> MessagePurpose;
@@ -139,7 +139,7 @@ pub struct DataRequest<TYPES: NodeType> {
     /// Request
     pub request: RequestKind<TYPES>,
     /// View this message is for
-    pub view: TYPES::Time,
+    pub view: TYPES::View,
     /// signature of the Sha256 hash of the data so outsiders can't use know
     /// public keys with stake.
     pub signature: <TYPES::SignatureKey as SignatureKey>::PureAssembledSignatureType,
@@ -149,11 +149,11 @@ pub struct DataRequest<TYPES: NodeType> {
 #[derive(Serialize, Deserialize, Derivative, Clone, Debug, PartialEq, Eq, Hash)]
 pub enum RequestKind<TYPES: NodeType> {
     /// Request VID data by our key and the VID commitment
-    Vid(TYPES::Time, TYPES::SignatureKey),
+    Vid(TYPES::View, TYPES::SignatureKey),
     /// Request a DA proposal for a certain view
-    DaProposal(TYPES::Time),
+    DaProposal(TYPES::View),
     /// Request for quorum proposal for a view
-    Proposal(TYPES::Time),
+    Proposal(TYPES::View),
 }
 
 /// A response for a request.  `SequencingMessage` is the same as other network messages
@@ -271,8 +271,12 @@ pub trait ConnectedNetwork<K: SignatureKey + 'static>: Clone + Send + Sync + 'st
 
     /// Update view can be used for any reason, but mostly it's for canceling tasks,
     /// and looking up the address of the leader of a future view.
-    async fn update_view<'a, TYPES>(&'a self, _view: u64, _membership: &TYPES::Membership)
-    where
+    async fn update_view<'a, TYPES>(
+        &'a self,
+        _view: u64,
+        _epoch: u64,
+        _membership: &TYPES::Membership,
+    ) where
         TYPES: NodeType<SignatureKey = K> + 'a,
     {
     }
diff --git a/crates/types/src/traits/node_implementation.rs b/crates/types/src/traits/node_implementation.rs
index 060df7adf3..c84031218c 100644
--- a/crates/types/src/traits/node_implementation.rs
+++ b/crates/types/src/traits/node_implementation.rs
@@ -210,7 +210,9 @@ pub trait NodeType:
     /// The time type that this hotshot setup is using.
     ///
     /// This should be the same `Time` that `ValidatedState::Time` is using.
-    type Time: ConsensusTime + Display;
+    type View: ConsensusTime + Display;
+    /// Same as above but for epoch.
+    type Epoch: ConsensusTime + Display;
     /// The AuctionSolverResult is a type that holds the data associated with a particular solver
     /// run, for a particular view.
     type AuctionResult: Debug
@@ -244,7 +246,7 @@ pub trait NodeType:
     type InstanceState: InstanceState;
 
     /// The validated state type that this hotshot setup is using.
-    type ValidatedState: ValidatedState<Self, Instance = Self::InstanceState, Time = Self::Time>;
+    type ValidatedState: ValidatedState<Self, Instance = Self::InstanceState, Time = Self::View>;
 
     /// Membership used for this implementation
     type Membership: Membership<Self>;
diff --git a/crates/types/src/traits/storage.rs b/crates/types/src/traits/storage.rs
index c11ba771b3..d400ce455b 100644
--- a/crates/types/src/traits/storage.rs
+++ b/crates/types/src/traits/storage.rs
@@ -36,7 +36,7 @@ pub trait Storage<TYPES: NodeType>: Send + Sync + Clone {
         proposal: &Proposal<TYPES, QuorumProposal<TYPES>>,
     ) -> Result<()>;
     /// Record a HotShotAction taken.
-    async fn record_action(&self, view: TYPES::Time, action: HotShotAction) -> Result<()>;
+    async fn record_action(&self, view: TYPES::View, action: HotShotAction) -> Result<()>;
     /// Update the current high QC in storage.
     async fn update_high_qc(&self, high_qc: QuorumCertificate<TYPES>) -> Result<()>;
     /// Update the currently undecided state of consensus.  This includes the undecided leaf chain,
@@ -44,7 +44,7 @@ pub trait Storage<TYPES: NodeType>: Send + Sync + Clone {
     async fn update_undecided_state(
         &self,
         leafs: CommitmentMap<Leaf<TYPES>>,
-        state: BTreeMap<TYPES::Time, View<TYPES>>,
+        state: BTreeMap<TYPES::View, View<TYPES>>,
     ) -> Result<()>;
     /// Upgrade the current decided upgrade certificate in storage.
     async fn update_decided_upgrade_certificate(
diff --git a/crates/types/src/utils.rs b/crates/types/src/utils.rs
index 8795ab028a..e3d19a8286 100644
--- a/crates/types/src/utils.rs
+++ b/crates/types/src/utils.rs
@@ -150,7 +150,7 @@ pub struct View<TYPES: NodeType> {
 #[derive(Debug, Clone)]
 pub struct RoundFinishedEvent<TYPES: NodeType> {
     /// The round that finished
-    pub view_number: TYPES::Time,
+    pub view_number: TYPES::View,
 }
 
 /// Whether or not to stop inclusively or exclusively when walking
diff --git a/crates/types/src/vote.rs b/crates/types/src/vote.rs
index 1376aa0d03..882512eae9 100644
--- a/crates/types/src/vote.rs
+++ b/crates/types/src/vote.rs
@@ -48,7 +48,7 @@ pub trait Vote<TYPES: NodeType>: HasViewNumber<TYPES> {
 /// Any type that is associated with a view
 pub trait HasViewNumber<TYPES: NodeType> {
     /// Returns the view number the type refers to.
-    fn view_number(&self) -> TYPES::Time;
+    fn view_number(&self) -> TYPES::View;
 }
 
 /**
@@ -68,13 +68,14 @@ pub trait Certificate<TYPES: NodeType>: HasViewNumber<TYPES> {
         vote_commitment: Commitment<VersionedVoteData<TYPES, Self::Voteable, V>>,
         data: Self::Voteable,
         sig: <TYPES::SignatureKey as SignatureKey>::QcType,
-        view: TYPES::Time,
+        view: TYPES::View,
     ) -> Self;
 
-    /// Checks if the cert is valid
+    /// Checks if the cert is valid in the given epoch
     fn is_valid_cert<MEMBERSHIP: Membership<TYPES>, V: Versions>(
         &self,
         membership: &MEMBERSHIP,
+        epoch: TYPES::Epoch,
         upgrade_lock: &UpgradeLock<TYPES, V>,
     ) -> impl std::future::Future<Output = bool>;
     /// Returns the amount of stake needed to create this certificate
@@ -130,12 +131,14 @@ impl<
         V: Versions,
     > VoteAccumulator<TYPES, VOTE, CERT, V>
 {
-    /// Add a vote to the total accumulated votes.  Returns the accumulator or the certificate if we
+    /// Add a vote to the total accumulated votes for the given epoch.
+    /// Returns the accumulator or the certificate if we
     /// have accumulated enough votes to exceed the threshold for creating a certificate.
     pub async fn accumulate(
         &mut self,
         vote: &VOTE,
         membership: &TYPES::Membership,
+        epoch: TYPES::Epoch,
     ) -> Either<(), CERT> {
         let key = vote.signing_key();
 
@@ -158,10 +161,10 @@ impl<
             return Either::Left(());
         }
 
-        let Some(stake_table_entry) = membership.stake(&key) else {
+        let Some(stake_table_entry) = membership.stake(&key, epoch) else {
             return Either::Left(());
         };
-        let stake_table = membership.stake_table();
+        let stake_table = membership.stake_table(epoch);
         let Some(vote_node_id) = stake_table
             .iter()
             .position(|x| *x == stake_table_entry.clone())
@@ -184,7 +187,7 @@ impl<
         let (signers, sig_list) = self
             .signers
             .entry(vote_commitment)
-            .or_insert((bitvec![0; membership.total_nodes()], Vec::new()));
+            .or_insert((bitvec![0; membership.total_nodes(epoch)], Vec::new()));
         if signers.get(vote_node_id).as_deref() == Some(&true) {
             error!("Node id is already in signers list");
             return Either::Left(());