diff --git a/Sources/AblyChat/ChatAPI.swift b/Sources/AblyChat/ChatAPI.swift
index 2927f860..0d03d6a3 100644
--- a/Sources/AblyChat/ChatAPI.swift
+++ b/Sources/AblyChat/ChatAPI.swift
@@ -128,6 +128,7 @@ internal final class ChatAPI: Sendable {
         }
 
         // (CHA-M8c) An update operation has PUT semantics. If a field is not specified in the update, it is assumed to be removed.
+        // CHA-M8c is not actually respected here, see https://github.com/ably/ably-chat-swift/issues/333
         let response: UpdateMessageResponse = try await makeRequest(endpoint, method: "PUT", body: .jsonObject(body))
 
         // response.timestamp is in milliseconds, convert it to seconds
@@ -177,10 +178,10 @@ internal final class ChatAPI: Sendable {
             serial: message.serial,
             action: .delete,
             clientID: message.clientID,
-            text: message.text,
+            text: "", // CHA-M9b (When a message is deleted successfully via the REST API, the caller shall receive a struct representing the Message in response, as if it were received via Realtime event.) Currently realtime sends an empty text for deleted message, so set it to empty text here as well.
             createdAt: message.createdAt,
-            metadata: message.metadata,
-            headers: message.headers,
+            metadata: [:], // CHA-M9b
+            headers: [:], // CHA-M9b
             version: response.version,
             timestamp: Date(timeIntervalSince1970: timestampInSeconds),
             operation: .init(
diff --git a/Tests/AblyChatTests/DefaultMessagesTests.swift b/Tests/AblyChatTests/DefaultMessagesTests.swift
index 96b87333..9151f83a 100644
--- a/Tests/AblyChatTests/DefaultMessagesTests.swift
+++ b/Tests/AblyChatTests/DefaultMessagesTests.swift
@@ -9,8 +9,12 @@ struct DefaultMessagesTests {
     // @spec CHA-M3a
     // @spec CHA-M3b
     // @spec CHA-M3f
+    // @spec CHA-M8a
+    // @spec CHA-M8b
+    // @spec CHA-M9a
+    // @spec CHA-M9b
     @Test
-    func clientMaySendMessageViaRESTChatAPI() async throws {
+    func sendAndUpdateAndDeleteMessageInTheRoom() async throws {
         // Given
         let realtime = MockRealtime {
             MockHTTPPaginatedResponse.successSendMessage
@@ -20,19 +24,50 @@ struct DefaultMessagesTests {
         let defaultMessages = DefaultMessages(channel: channel, chatAPI: chatAPI, roomName: "basketball", clientID: "clientId", logger: TestLogger())
 
         // When
-        _ = try await defaultMessages.send(params: .init(text: "hey"))
+        let sentMessage = try await defaultMessages.send(params: .init(text: "hey", metadata: ["key1": "val1"], headers: ["key2": "val2"]))
 
         // Then
+        #expect(sentMessage.text == "hey")
+        #expect(sentMessage.metadata == ["key1": "val1"])
+        #expect(sentMessage.headers == ["key2": "val2"])
         #expect(realtime.callRecorder.hasRecord(
             matching: "request(_:path:params:body:headers:)",
-            arguments: ["method": "POST", "path": "/chat/v3/rooms/basketball/messages", "body": ["text": "hey"], "params": [:], "headers": [:]]
+            arguments: ["method": "POST", "path": "/chat/v3/rooms/basketball/messages", "body": ["text": "hey", "metadata": ["key1": "val1"], "headers": ["key2": "val2"]], "params": [:], "headers": [:]]
+        )
+        )
+
+        // When
+        var newMessage = sentMessage
+        newMessage.text = "hey!" // see https://github.com/ably/ably-chat-swift/issues/333
+        let updatedMessage = try await defaultMessages.update(newMessage: newMessage, description: "add exclamation", metadata: ["key3": "val3"])
+
+        // Then
+        #expect(updatedMessage.text == "hey!")
+        #expect(updatedMessage.operation?.metadata == ["key3": "val3"])
+        #expect(updatedMessage.operation?.description == "add exclamation")
+        #expect(realtime.callRecorder.hasRecord(
+            matching: "request(_:path:params:body:headers:)",
+            arguments: ["method": "PUT", "path": "/chat/v3/rooms/basketball/messages/\(sentMessage.serial)", "body": ["message": ["text": "hey!", "metadata": ["key1": "val1"], "headers": ["key2": "val2"]], "description": "add exclamation", "metadata": ["key3": "val3"]], "params": [:], "headers": [:]]
+        )
+        )
+
+        // When
+        let deletedMessage = try await defaultMessages.delete(message: sentMessage, params: .init())
+
+        // Then
+        #expect(deletedMessage.text.isEmpty)
+        #expect(deletedMessage.headers.isEmpty)
+        #expect(deletedMessage.metadata.isEmpty)
+        #expect(realtime.callRecorder.hasRecord(
+            matching: "request(_:path:params:body:headers:)",
+            arguments: ["method": "POST", "path": "/chat/v3/rooms/basketball/messages/\(sentMessage.serial)/delete", "body": [:], "params": [:], "headers": [:]]
         )
         )
     }
 
     // @spec CHA-M3e
     @Test
-    func errorShouldBeThrownIfErrorIsReturnedFromRESTChatAPI() async throws {
+    func errorShouldBeThrownIfErrorIsReturnedFromSendRESTChatAPI() async throws {
         // Given
         let realtime = MockRealtime { @Sendable () throws(ARTErrorInfo) in
             throw ARTErrorInfo(domain: "SomeDomain", code: 123)
@@ -53,12 +88,60 @@ struct DefaultMessagesTests {
         }
     }
 
+    // @spec CHA-M8d
+    @Test
+    func errorShouldBeThrownIfErrorIsReturnedFromUpdateRESTChatAPI() async throws {
+        // Given
+        let realtime = MockRealtime { @Sendable () throws(ARTErrorInfo) in
+            throw ARTErrorInfo(domain: "SomeDomain", code: 123)
+        }
+        let chatAPI = ChatAPI(realtime: realtime)
+        let channel = MockRealtimeChannel()
+        let defaultMessages = DefaultMessages(channel: channel, chatAPI: chatAPI, roomName: "basketball", clientID: "clientId", logger: TestLogger())
+
+        // Then
+        // TODO: avoids compiler crash (https://github.com/ably/ably-chat-swift/issues/233), revert once Xcode 16.3 released
+        let doIt = {
+            let message = try Message(jsonObject: ["serial": "0", "version": "0", "text": "hey", "clientId": "0", "action": "message.update", "metadata": [:], "headers": [:]]) // arbitrary
+            _ = try await defaultMessages.update(newMessage: message, description: "", metadata: [:])
+        }
+        await #expect {
+            try await doIt()
+        } throws: { error in
+            error as? ARTErrorInfo == ARTErrorInfo(domain: "SomeDomain", code: 123)
+        }
+    }
+
+    // @spec CHA-M9c
+    @Test
+    func errorShouldBeThrownIfErrorIsReturnedFromDeleteRESTChatAPI() async throws {
+        // Given
+        let realtime = MockRealtime { @Sendable () throws(ARTErrorInfo) in
+            throw ARTErrorInfo(domain: "SomeDomain", code: 123)
+        }
+        let chatAPI = ChatAPI(realtime: realtime)
+        let channel = MockRealtimeChannel()
+        let defaultMessages = DefaultMessages(channel: channel, chatAPI: chatAPI, roomName: "basketball", clientID: "clientId", logger: TestLogger())
+
+        // Then
+        // TODO: avoids compiler crash (https://github.com/ably/ably-chat-swift/issues/233), revert once Xcode 16.3 released
+        let doIt = {
+            let message = try Message(jsonObject: ["serial": "0", "version": "0", "text": "hey", "clientId": "0", "action": "message.update", "metadata": [:], "headers": [:]]) // arbitrary
+            _ = try await defaultMessages.delete(message: message, params: .init())
+        }
+        await #expect {
+            try await doIt()
+        } throws: { error in
+            error as? ARTErrorInfo == ARTErrorInfo(domain: "SomeDomain", code: 123)
+        }
+    }
+
     // @spec CHA-M5a
     @Test
     func subscriptionPointIsChannelSerialWhenUnderlyingRealtimeChannelIsAttached() async throws {
         // Given
         let realtime = MockRealtime {
-            MockHTTPPaginatedResponse.successSendMessageWithNoItems
+            MockHTTPPaginatedResponse.successGetMessagesWithNoItems
         }
         let channelSerial = "123"
         let chatAPI = ChatAPI(realtime: realtime)
@@ -83,7 +166,7 @@ struct DefaultMessagesTests {
     func subscriptionPointIsAttachSerialWhenUnderlyingRealtimeChannelIsNotAttached() async throws {
         // Given
         let realtime = MockRealtime {
-            MockHTTPPaginatedResponse.successSendMessageWithNoItems
+            MockHTTPPaginatedResponse.successGetMessagesWithNoItems
         }
         let attachSerial = "attach123"
         let chatAPI = ChatAPI(realtime: realtime)
@@ -113,7 +196,7 @@ struct DefaultMessagesTests {
         let attachSerial = "attach123"
         let channelSerial = "channel456"
         let realtime = MockRealtime {
-            MockHTTPPaginatedResponse.successSendMessageWithNoItems
+            MockHTTPPaginatedResponse.successGetMessagesWithNoItems
         }
         let chatAPI = ChatAPI(realtime: realtime)
         let channel = MockRealtimeChannel(
@@ -157,7 +240,7 @@ struct DefaultMessagesTests {
         let attachSerial = "attach123"
         let channelSerial = "channel456"
         let realtime = MockRealtime {
-            MockHTTPPaginatedResponse.successSendMessageWithNoItems
+            MockHTTPPaginatedResponse.successGetMessagesWithNoItems
         }
         let chatAPI = ChatAPI(realtime: realtime)
         let channel = MockRealtimeChannel(
diff --git a/Tests/AblyChatTests/Mocks/MockHTTPPaginatedResponse.swift b/Tests/AblyChatTests/Mocks/MockHTTPPaginatedResponse.swift
index 8da0c873..5f78f536 100644
--- a/Tests/AblyChatTests/Mocks/MockHTTPPaginatedResponse.swift
+++ b/Tests/AblyChatTests/Mocks/MockHTTPPaginatedResponse.swift
@@ -59,6 +59,8 @@ extension MockHTTPPaginatedResponse {
         items: [
             [
                 "serial": "3446456",
+                "version": "3446456",
+                "timestamp": 1_631_840_000_000,
                 "createdAt": 1_631_840_000_000,
                 "text": "hello",
             ],