diff --git a/android/composeui/src/main/java/com/stadiamaps/ferrostar/composeui/formatting/DateTimeFormatter.kt b/android/composeui/src/main/java/com/stadiamaps/ferrostar/composeui/formatting/DateTimeFormatter.kt
index 020fe50f..8576731c 100644
--- a/android/composeui/src/main/java/com/stadiamaps/ferrostar/composeui/formatting/DateTimeFormatter.kt
+++ b/android/composeui/src/main/java/com/stadiamaps/ferrostar/composeui/formatting/DateTimeFormatter.kt
@@ -1,6 +1,7 @@
 package com.stadiamaps.ferrostar.composeui.formatting
 
 import android.icu.util.ULocale
+import java.time.format.FormatStyle
 import java.util.Locale
 import kotlinx.datetime.LocalDateTime
 import kotlinx.datetime.toJavaLocalDateTime
@@ -11,12 +12,11 @@ interface DateTimeFormatter {
 
 class EstimatedArrivalDateTimeFormatter(
     private var localeOverride: ULocale? = null,
+    private val unitStyle: FormatStyle = FormatStyle.SHORT
 ) : DateTimeFormatter {
   override fun format(dateTime: LocalDateTime): String {
     val locale = localeOverride?.let { Locale(it.language, it.country) } ?: Locale.getDefault()
-    val formatter =
-        java.time.format.DateTimeFormatter.ofLocalizedTime(java.time.format.FormatStyle.SHORT)
-            .withLocale(locale)
+    val formatter = java.time.format.DateTimeFormatter.ofLocalizedTime(unitStyle).withLocale(locale)
     return formatter.format(dateTime.toJavaLocalDateTime())
   }
 }
diff --git a/android/core/src/main/java/com/stadiamaps/ferrostar/core/NavigationViewModel.kt b/android/core/src/main/java/com/stadiamaps/ferrostar/core/NavigationViewModel.kt
index 7dbd9121..86a6448b 100644
--- a/android/core/src/main/java/com/stadiamaps/ferrostar/core/NavigationViewModel.kt
+++ b/android/core/src/main/java/com/stadiamaps/ferrostar/core/NavigationViewModel.kt
@@ -104,7 +104,7 @@ interface NavigationViewModel {
  * interface that is reused across navigation sessions will probably need to craft their own view
  * model.
  */
-class DefaultNavigationViewModel(
+open class DefaultNavigationViewModel(
     private val ferrostarCore: FerrostarCore,
     private val annotationPublisher: AnnotationPublisher<*> = NoOpAnnotationPublisher()
 ) : ViewModel(), NavigationViewModel {