diff --git a/Source/ARTAnnotation.m b/Source/ARTAnnotation.m
index 53f35d2c9..4ce0f0c6e 100644
--- a/Source/ARTAnnotation.m
+++ b/Source/ARTAnnotation.m
@@ -36,6 +36,29 @@ - (instancetype)initWithId:(NSString *)annotationId
     return self;
 }
 
+- (instancetype)initWithId:(nullable NSString *)annotationId
+                    action:(ARTAnnotationAction)action
+                  clientId:(nullable NSString *)clientId
+                      name:(nullable NSString *)name
+                     count:(nullable NSNumber *)count
+                      data:(nullable id)data
+             messageSerial:(NSString *)messageSerial
+                      type:(NSString *)type
+                    extras:(nullable id<ARTJsonCompatible>)extras {
+    if (self = [self init]) {
+        _id = annotationId;
+        _action = action;
+        _clientId = clientId;
+        _name = name;
+        _count = count;
+        _data = data;
+        _messageSerial = messageSerial;
+        _type = type;
+        _extras = extras;
+    }
+    return self;
+}
+
 - (NSString *)description {
     NSMutableString *description = [[super description] mutableCopy];
     [description deleteCharactersInRange:NSMakeRange(description.length - (description.length>2 ? 2:0), 2)];
diff --git a/Source/ARTJsonLikeEncoder.m b/Source/ARTJsonLikeEncoder.m
index 69fad01d2..b5890a4d4 100644
--- a/Source/ARTJsonLikeEncoder.m
+++ b/Source/ARTJsonLikeEncoder.m
@@ -473,7 +473,7 @@ - (ARTAnnotation *)annotationFromDictionary:(NSDictionary *)input {
                                                             count:[input artNumber:@"count"]
                                                              data:[input objectForKey:@"data"]
                                                          encoding:[input artString:@"encoding"]
-                                                        timestamp:[input artTimestamp:@"timestamp"]
+                                                        timestamp:[input artTimestamp:@"timestamp"] ?: NSDate.date // see https://github.com/ably/ably-cocoa/issues/2124
                                                            serial:[input artString:@"serial"]
                                                     messageSerial:[input artString:@"messageSerial"]
                                                              type:[input artString:@"type"]
diff --git a/Source/ARTRealtimeAnnotations.m b/Source/ARTRealtimeAnnotations.m
index 072a08cec..e31327e9b 100644
--- a/Source/ARTRealtimeAnnotations.m
+++ b/Source/ARTRealtimeAnnotations.m
@@ -134,9 +134,6 @@ - (void)publishAnnotation:(ARTOutboundAnnotation *)outboundAnnotation
                                                              name:outboundAnnotation.name
                                                             count:outboundAnnotation.count
                                                              data:outboundAnnotation.data
-                                                         encoding:nil
-                                                        timestamp:nil
-                                                           serial:nil
                                                     messageSerial:messageSerial // RSAN1c2
                                                              type:outboundAnnotation.type
                                                            extras:outboundAnnotation.extras];
@@ -157,7 +154,7 @@ - (void)publishAnnotation:(ARTOutboundAnnotation *)outboundAnnotation
     if (annotationSize > maxSize) {
         if (callback) {
             callback([ARTErrorInfo createWithCode:ARTErrorMaxMessageLengthExceeded
-                                       message:[NSString stringWithFormat:@"Annotation size of %ld bytes exceeds maxMessageSize of %ld bytes", (long)annotationSize, (long)maxSize]]);
+                                          message:[NSString stringWithFormat:@"Annotation size of %ld bytes exceeds maxMessageSize of %ld bytes", (long)annotationSize, (long)maxSize]]);
         }
         return;
     }
diff --git a/Source/ARTRestAnnotations.m b/Source/ARTRestAnnotations.m
index 62db9ef48..fea0cd819 100644
--- a/Source/ARTRestAnnotations.m
+++ b/Source/ARTRestAnnotations.m
@@ -149,9 +149,6 @@ - (void)publishAnnotation:(ARTOutboundAnnotation *)outboundAnnotation
                                                              name:outboundAnnotation.name
                                                             count:outboundAnnotation.count
                                                              data:outboundAnnotation.data
-                                                         encoding:nil
-                                                        timestamp:nil
-                                                           serial:nil
                                                     messageSerial:messageSerial // RSAN1c2
                                                              type:outboundAnnotation.type
                                                            extras:outboundAnnotation.extras];
diff --git a/Source/PrivateHeaders/Ably/ARTAnnotation+Private.h b/Source/PrivateHeaders/Ably/ARTAnnotation+Private.h
index e543f12cd..4866f6a59 100644
--- a/Source/PrivateHeaders/Ably/ARTAnnotation+Private.h
+++ b/Source/PrivateHeaders/Ably/ARTAnnotation+Private.h
@@ -13,6 +13,19 @@ NS_ASSUME_NONNULL_BEGIN
 
 - (NSInteger)annotationSize;
 
+/**
+ * Internal initializer for converting outbound annotations to annotations before publishing
+ */
+- (instancetype)initWithId:(nullable NSString *)annotationId
+                    action:(ARTAnnotationAction)action
+                  clientId:(nullable NSString *)clientId
+                      name:(nullable NSString *)name
+                     count:(nullable NSNumber *)count
+                      data:(nullable id)data
+             messageSerial:(NSString *)messageSerial
+                      type:(NSString *)type
+                    extras:(nullable id<ARTJsonCompatible>)extras;
+
 @end
 
 NS_ASSUME_NONNULL_END
diff --git a/Source/include/Ably/ARTAnnotation.h b/Source/include/Ably/ARTAnnotation.h
index 3a5050b4a..644ffa1b5 100644
--- a/Source/include/Ably/ARTAnnotation.h
+++ b/Source/include/Ably/ARTAnnotation.h
@@ -47,7 +47,7 @@ NS_SWIFT_SENDABLE
 @property (nonatomic, readonly, nullable) NSString *encoding;
 
 /// Timestamp of when the message was received by Ably, as a `NSDate` object.
-@property (nullable, nonatomic, readonly) NSDate *timestamp;
+@property (readonly, nonatomic) NSDate *timestamp;
 
 /// This annotation's unique serial (lexicographically totally ordered).
 @property (readonly, nonatomic) NSString *serial;
@@ -68,7 +68,7 @@ NS_SWIFT_SENDABLE
                      count:(nullable NSNumber *)count
                       data:(nullable id)data
                   encoding:(nullable NSString *)encoding
-                 timestamp:(nullable NSDate *)timestamp
+                 timestamp:(NSDate *)timestamp
                     serial:(nullable NSString *)serial
              messageSerial:(NSString *)messageSerial
                       type:(NSString *)type