diff --git a/Source/ARTRealtimeChannel.m b/Source/ARTRealtimeChannel.m
index c5fbfd2b9..dedd744d7 100644
--- a/Source/ARTRealtimeChannel.m
+++ b/Source/ARTRealtimeChannel.m
@@ -153,19 +153,19 @@ - (void)detach:(nullable ARTCallback)callback {
     [_internal detach:callback];
 }
 
-- (ARTEventListener *_Nullable)subscribe:(ARTMessageCallback)callback {
+- (ARTEventListener *)subscribe:(ARTMessageCallback)callback {
     return [_internal subscribe:callback];
 }
 
-- (ARTEventListener *_Nullable)subscribeWithAttachCallback:(nullable ARTCallback)onAttach callback:(ARTMessageCallback)cb {
+- (ARTEventListener *)subscribeWithAttachCallback:(nullable ARTCallback)onAttach callback:(ARTMessageCallback)cb {
     return [_internal subscribeWithAttachCallback:onAttach callback:cb];
 }
 
-- (ARTEventListener *_Nullable)subscribe:(NSString *)name callback:(ARTMessageCallback)cb {
+- (ARTEventListener *)subscribe:(NSString *)name callback:(ARTMessageCallback)cb {
     return [_internal subscribe:name callback:cb];
 }
 
-- (ARTEventListener *_Nullable)subscribe:(NSString *)name onAttach:(nullable ARTCallback)onAttach callback:(ARTMessageCallback)cb {
+- (ARTEventListener *)subscribe:(NSString *)name onAttach:(nullable ARTCallback)onAttach callback:(ARTMessageCallback)cb {
     return [_internal subscribe:name onAttach:onAttach callback:cb];
 }
 
diff --git a/Source/ARTRealtimePresence.m b/Source/ARTRealtimePresence.m
index aa5770e8c..bd359375d 100644
--- a/Source/ARTRealtimePresence.m
+++ b/Source/ARTRealtimePresence.m
@@ -105,19 +105,19 @@ - (void)leaveClient:(NSString *)clientId data:(id _Nullable)data callback:(nulla
     [_internal leaveClient:clientId data:data callback:cb];
 }
 
-- (ARTEventListener *_Nullable)subscribe:(ARTPresenceMessageCallback)callback {
+- (ARTEventListener *)subscribe:(ARTPresenceMessageCallback)callback {
     return [_internal subscribe:callback];
 }
 
-- (ARTEventListener *_Nullable)subscribeWithAttachCallback:(nullable ARTCallback)onAttach callback:(ARTPresenceMessageCallback)cb {
+- (ARTEventListener *)subscribeWithAttachCallback:(nullable ARTCallback)onAttach callback:(ARTPresenceMessageCallback)cb {
     return [_internal subscribeWithAttachCallback:onAttach callback:cb];
 }
 
-- (ARTEventListener *_Nullable)subscribe:(ARTPresenceAction)action callback:(ARTPresenceMessageCallback)cb {
+- (ARTEventListener *)subscribe:(ARTPresenceAction)action callback:(ARTPresenceMessageCallback)cb {
     return [_internal subscribe:action callback:cb];
 }
 
-- (ARTEventListener *_Nullable)subscribe:(ARTPresenceAction)action onAttach:(nullable ARTCallback)onAttach callback:(ARTPresenceMessageCallback)cb {
+- (ARTEventListener *)subscribe:(ARTPresenceAction)action onAttach:(nullable ARTCallback)onAttach callback:(ARTPresenceMessageCallback)cb {
     return [_internal subscribe:action onAttach:onAttach callback:cb];
 }
 
diff --git a/Source/include/Ably/ARTRealtimeChannel.h b/Source/include/Ably/ARTRealtimeChannel.h
index 1d9a628a5..70375d4e9 100644
--- a/Source/include/Ably/ARTRealtimeChannel.h
+++ b/Source/include/Ably/ARTRealtimeChannel.h
@@ -76,7 +76,7 @@ NS_ASSUME_NONNULL_BEGIN
  *
  * @see See `subscribeWithAttachCallback:` for more details.
  */
-- (ARTEventListener *_Nullable)subscribe:(ARTMessageCallback)callback;
+- (ARTEventListener *)subscribe:(ARTMessageCallback)callback;
 
 /**
  * Registers a listener for messages on this channel. The caller supplies a listener function, which is called each time one or more messages arrives on the channel.
@@ -87,7 +87,7 @@ NS_ASSUME_NONNULL_BEGIN
  *
  * @return An `ARTEventListener` object.
  */
-- (ARTEventListener *_Nullable)subscribeWithAttachCallback:(nullable ARTCallback)onAttach callback:(ARTMessageCallback)callback;
+- (ARTEventListener *)subscribeWithAttachCallback:(nullable ARTCallback)onAttach callback:(ARTMessageCallback)callback;
 
 /**
  * Registers a listener for messages with a given event `name` on this channel. The caller supplies a listener function, which is called each time one or more matching messages arrives on the channel.
@@ -99,7 +99,7 @@ NS_ASSUME_NONNULL_BEGIN
  *
  * @see See `subscribeWithAttachCallback:` for more details.
 */
-- (ARTEventListener *_Nullable)subscribe:(NSString *)name callback:(ARTMessageCallback)callback;
+- (ARTEventListener *)subscribe:(NSString *)name callback:(ARTMessageCallback)callback;
 
 /**
  * Registers a listener for messages with a given event `name` on this channel. The caller supplies a listener function, which is called each time one or more matching messages arrives on the channel. A callback may optionally be passed in to this call to be notified of success or failure of the channel `-[ARTRealtimeChannelProtocol attach]` operation. It will not be called if the `ARTRealtimeChannelOptions.attachOnSubscribe` channel option is set to `false`.
@@ -109,7 +109,7 @@ NS_ASSUME_NONNULL_BEGIN
  *
  * @return An `ARTEventListener` object.
  */
-- (ARTEventListener *_Nullable)subscribe:(NSString *)name onAttach:(nullable ARTCallback)onAttach callback:(ARTMessageCallback)callback;
+- (ARTEventListener *)subscribe:(NSString *)name onAttach:(nullable ARTCallback)onAttach callback:(ARTMessageCallback)callback;
 
 /**
  * Deregisters all listeners to messages on this channel. This removes all earlier subscriptions.
diff --git a/Source/include/Ably/ARTRealtimePresence.h b/Source/include/Ably/ARTRealtimePresence.h
index f90fb644c..5e03252a8 100644
--- a/Source/include/Ably/ARTRealtimePresence.h
+++ b/Source/include/Ably/ARTRealtimePresence.h
@@ -142,7 +142,7 @@ NS_ASSUME_NONNULL_BEGIN
  *
  * @return An event listener object.
  */
-- (ARTEventListener *_Nullable)subscribe:(ARTPresenceMessageCallback)callback;
+- (ARTEventListener *)subscribe:(ARTPresenceMessageCallback)callback;
 
 /**
  * Registers a listener that is called each time a `ARTPresenceMessage` is received on the channel, such as a new member entering the presence set. A callback may optionally be passed in to this call to be notified of success or failure of the channel `-[ARTRealtimeChannelProtocol attach]` operation. It will not be called if the `ARTRealtimeChannelOptions.attachOnSubscribe` channel option is set to `false`.
@@ -152,7 +152,7 @@ NS_ASSUME_NONNULL_BEGIN
  *
  * @return An event listener object.
  */
-- (ARTEventListener *_Nullable)subscribeWithAttachCallback:(nullable ARTCallback)onAttach callback:(ARTPresenceMessageCallback)callback;
+- (ARTEventListener *)subscribeWithAttachCallback:(nullable ARTCallback)onAttach callback:(ARTPresenceMessageCallback)callback;
 
 /**
  * Registers a listener that is called each time a `ARTPresenceMessage` matching a given `ARTPresenceAction` is received on the channel, such as a new member entering the presence set.
@@ -162,7 +162,7 @@ NS_ASSUME_NONNULL_BEGIN
  *
  * @return An event listener object.
  */
-- (ARTEventListener *_Nullable)subscribe:(ARTPresenceAction)action callback:(ARTPresenceMessageCallback)callback;
+- (ARTEventListener *)subscribe:(ARTPresenceAction)action callback:(ARTPresenceMessageCallback)callback;
 
 /**
  * Registers a listener that is called each time a `ARTPresenceMessage` matching a given `ARTPresenceAction` is received on the channel, such as a new member entering the presence set. A callback may optionally be passed in to this call to be notified of success or failure of the channel `-[ARTRealtimeChannelProtocol attach]` operation. It will not be called if the `ARTRealtimeChannelOptions.attachOnSubscribe` channel option is set to `false`.
@@ -173,7 +173,7 @@ NS_ASSUME_NONNULL_BEGIN
  *
  * @return An event listener object.
  */
-- (ARTEventListener *_Nullable)subscribe:(ARTPresenceAction)action onAttach:(nullable ARTCallback)onAttach callback:(ARTPresenceMessageCallback)callback;
+- (ARTEventListener *)subscribe:(ARTPresenceAction)action onAttach:(nullable ARTCallback)onAttach callback:(ARTPresenceMessageCallback)callback;
 
 /**
  * Deregisters all listeners currently receiving `ARTPresenceMessage` for the channel.
diff --git a/Test/Tests/RealtimeClientPresenceTests.swift b/Test/Tests/RealtimeClientPresenceTests.swift
index 66a8be6b7..09f9a25c1 100644
--- a/Test/Tests/RealtimeClientPresenceTests.swift
+++ b/Test/Tests/RealtimeClientPresenceTests.swift
@@ -497,7 +497,7 @@ class RealtimeClientPresenceTests: XCTestCase {
         defer { client.dispose(); client.close() }
         let channel = client.channels.get(test.uniqueChannelName())
 
-        let listener = channel.presence.subscribe { _ in }!
+        let listener = channel.presence.subscribe { _ in }
         XCTAssertEqual(channel.internal.internalPresence.eventEmitter.anyListeners.count, 1)
         channel.presence.unsubscribe(listener)
         XCTAssertEqual(channel.internal.internalPresence.eventEmitter.anyListeners.count, 0)
@@ -878,7 +878,7 @@ class RealtimeClientPresenceTests: XCTestCase {
         defer { client.dispose(); client.close() }
         let channel = client.channels.get(test.uniqueChannelName())
 
-        let listener = channel.presence.subscribe(.present) { _ in }!
+        let listener = channel.presence.subscribe(.present) { _ in }
         XCTAssertEqual(channel.internal.internalPresence.eventEmitter.listeners.count, 1)
         channel.presence.unsubscribe(.present, listener: listener)
         XCTAssertEqual(channel.internal.internalPresence.eventEmitter.listeners.count, 0)