chore: further detail

README.md

@@ -55,7 +55,8 @@ app.start();
     - It's also important to await any processing that you are doing to ensure that messages are processed one at a time.
 - By default, messages that are sent to the `handleMessage` and `handleMessageBatch` functions will be considered as processed if they return without an error.
     - To acknowledge individual messages, please return the message that you want to acknowledge if you are using `handleMessage` or the messages for `handleMessageBatch`.
-        - To also note, returning an object or an array will be considered an acknowledgement of no message(s) and will result in no messages being deleted.
+        - To note, returning an object or an array will be considered an acknowledgement of no message(s) and will result in no messages being deleted.
+        - By default, if an object or an array is not returned, all messages will be acknowledged.
 - Messages are deleted from the queue once the handler function has completed successfully (the above items should also be taken into account).
 
 ### Credentials