diff --git a/src/main/kotlin/StandardFrames.kt b/src/main/kotlin/StandardFrames.kt
index 3cc0e93..92b6b42 100644
--- a/src/main/kotlin/StandardFrames.kt
+++ b/src/main/kotlin/StandardFrames.kt
@@ -282,4 +282,12 @@ object StandardFrames {
       expireTimerVersion = 1
     )
   )
+
+  val chatReleaseNotes = Frame(
+    chat = Chat(
+      id = 4,
+      recipientId = recipientReleaseNotes.recipient!!.id,
+      expireTimerVersion = 1
+    )
+  )
 }
diff --git a/src/main/kotlin/tests/ChatItemSimpleUpdatesTestCase.kt b/src/main/kotlin/tests/ChatItemSimpleUpdatesTestCase.kt
index fd13709..a7d4654 100644
--- a/src/main/kotlin/tests/ChatItemSimpleUpdatesTestCase.kt
+++ b/src/main/kotlin/tests/ChatItemSimpleUpdatesTestCase.kt
@@ -29,36 +29,42 @@ object ChatItemSimpleUpdatesTestCase : TestCase("chat_item_simple_updates") {
     val selfRecipientId = StandardFrames.recipientSelf.recipient!!.id
     val aliceRecipientId = StandardFrames.recipientAlice.recipient!!.id
     val releaseNotesRecipientId = StandardFrames.recipientReleaseNotes.recipient!!.id
+    val aliceChatId = StandardFrames.chatAlice.chat!!.id
+    val releaseNotesChatId = StandardFrames.chatReleaseNotes.chat!!.id
 
     // Some simple chat updates can originate from the local user or a remote
     // user, while some are necessarily from one or the other.
-    val authorIds: List<Long> = when (simpleChatUpdate) {
+    val authorData: AuthorData = when (simpleChatUpdate) {
       // ...and release note donation requests should come from the release
       // notes recipient.
-      SimpleChatUpdate.Type.RELEASE_CHANNEL_DONATION_REQUEST -> listOf(releaseNotesRecipientId)
+      SimpleChatUpdate.Type.RELEASE_CHANNEL_DONATION_REQUEST -> AuthorData(releaseNotesRecipientId, releaseNotesChatId)
       SimpleChatUpdate.Type.IDENTITY_UPDATE,
       SimpleChatUpdate.Type.IDENTITY_VERIFIED,
       SimpleChatUpdate.Type.IDENTITY_DEFAULT,
       SimpleChatUpdate.Type.JOINED_SIGNAL,
-      SimpleChatUpdate.Type.CHANGE_NUMBER -> listOf(aliceRecipientId)
+      SimpleChatUpdate.Type.CHANGE_NUMBER -> AuthorData(aliceRecipientId, aliceChatId)
       SimpleChatUpdate.Type.CHAT_SESSION_REFRESH,
       SimpleChatUpdate.Type.REPORTED_SPAM,
       SimpleChatUpdate.Type.BLOCKED,
       SimpleChatUpdate.Type.UNBLOCKED,
-      SimpleChatUpdate.Type.MESSAGE_REQUEST_ACCEPTED -> listOf(selfRecipientId)
+      SimpleChatUpdate.Type.MESSAGE_REQUEST_ACCEPTED -> AuthorData(selfRecipientId, aliceChatId)
       SimpleChatUpdate.Type.END_SESSION,
       SimpleChatUpdate.Type.BAD_DECRYPT,
       SimpleChatUpdate.Type.PAYMENTS_ACTIVATED,
       SimpleChatUpdate.Type.PAYMENT_ACTIVATION_REQUEST,
-      SimpleChatUpdate.Type.UNSUPPORTED_PROTOCOL_MESSAGE -> listOf(selfRecipientId, aliceRecipientId)
+      SimpleChatUpdate.Type.UNSUPPORTED_PROTOCOL_MESSAGE -> AuthorData(listOf(selfRecipientId, aliceRecipientId), aliceChatId)
       // Impossible, checked above.
-      SimpleChatUpdate.Type.UNKNOWN -> listOf()
+      SimpleChatUpdate.Type.UNKNOWN -> throw AssertionError("Impossible")
     }
 
-    for ((idx, authorId) in authorIds.withIndex()) {
+    for ((idx, authorId) in authorData.possibleAuthorIds.withIndex()) {
+      if (authorData.chatId == releaseNotesChatId) {
+        frames += StandardFrames.chatReleaseNotes
+      }
+
       frames += Frame(
         chatItem = ChatItem(
-          chatId = StandardFrames.chatAlice.chat!!.id,
+          chatId = authorData.chatId,
           authorId = authorId,
           dateSent = dateSentTimestamps[idx],
           directionless = ChatItem.DirectionlessMessageDetails(),
@@ -69,4 +75,11 @@ object ChatItemSimpleUpdatesTestCase : TestCase("chat_item_simple_updates") {
       )
     }
   }
+
+  data class AuthorData(
+    val possibleAuthorIds: List<Long>,
+    val chatId: Long
+  ) {
+    constructor(authorId: Long, chatId: Long) : this(listOf(authorId), chatId)
+  }
 }
diff --git a/test-cases/chat_item_simple_updates_05.binproto b/test-cases/chat_item_simple_updates_05.binproto
index 50409bd..98dda81 100644
Binary files a/test-cases/chat_item_simple_updates_05.binproto and b/test-cases/chat_item_simple_updates_05.binproto differ
diff --git a/test-cases/chat_item_simple_updates_05.txtproto b/test-cases/chat_item_simple_updates_05.txtproto
index 51cb450..5810846 100644
--- a/test-cases/chat_item_simple_updates_05.txtproto
+++ b/test-cases/chat_item_simple_updates_05.txtproto
@@ -114,10 +114,18 @@ Frame {
   }
 }
 
+Frame {
+  chat = Chat {
+    expireTimerVersion = 1
+    id = 4
+    recipientId = 2
+  }
+}
+
 Frame {
   chatItem = ChatItem {
     authorId = 2
-    chatId = 2
+    chatId = 4
     dateSent = 1833527071197
     directionless = DirectionlessMessageDetails {}
     updateMessage = ChatUpdateMessage {