diff --git a/src/entities/SharedEntities.ts b/src/entities/SharedEntities.ts
index ad723c5..7e334f1 100644
--- a/src/entities/SharedEntities.ts
+++ b/src/entities/SharedEntities.ts
@@ -1,5 +1,5 @@
 export interface IEntityWithOptionalTimestamp {
-  millisecondsSinceEpoch?: number;
+  updateTimeMs?: number;
 }
 
 export interface IEntityWithId {
diff --git a/src/loaders/shuttle/ApiBasedShuttleRepositoryLoader.ts b/src/loaders/shuttle/ApiBasedShuttleRepositoryLoader.ts
index 062ff43..6b73887 100644
--- a/src/loaders/shuttle/ApiBasedShuttleRepositoryLoader.ts
+++ b/src/loaders/shuttle/ApiBasedShuttleRepositoryLoader.ts
@@ -221,7 +221,7 @@ export class ApiBasedShuttleRepositoryLoader implements ShuttleRepositoryLoader
             secondsRemaining: jsonEta.secondsSpent,
             shuttleId: `${shuttleId}`,
             stopId: stopId,
-            millisecondsSinceEpoch: Date.now(),
+            updateTimeMs: Date.now(),
             systemId: this.systemIdForConstructedData,
           };