diff --git a/lib/reducers/message-reducer.js b/lib/reducers/message-reducer.js
--- a/lib/reducers/message-reducer.js
+++ b/lib/reducers/message-reducer.js
@@ -602,7 +602,7 @@
   for (const keyserverID in newestMessageTimePerKeyserver) {
     currentAsOf[keyserverID] = Math.max(
       newestMessageTimePerKeyserver[keyserverID],
-      processedMessageStore.currentAsOf[keyserverID],
+      processedMessageStore.currentAsOf[keyserverID] ?? 0,
     );
   }