Add message conflation section to updates-deletes docs

src/pages/docs/messages/updates-deletes.mdx

@@ -604,6 +604,29 @@ When appending to a message, you can optionally provide metadata:
 
 This metadata will end up in the message's `version` property. See [Message version structure](/docs/messages/updates-deletes#version-structure) for what this looks like.
 
+## Message conflation <a id="message-conflation"/>
+
+When [server-side batching](/docs/messages/batch#server-side) or [message conflation](/docs/messages#conflation) is enabled, Ably groups update, delete, and append messages received in the configured time window before delivering them to subscribers.
+During this window, if multiple operations target the same message (identified by its `serial`), Ably combines them into a single operation.
+Instead of receiving every intermediate update, append, or delete, subscribers receive a single message representing the combined result.
+For update, delete, and append messages the same behavior applies whether you use batching rules or conflation rules.
+
+### Append conflation
+
+Ably concatenates a series of appends to the same message into a single larger append. Subscribers receive one append containing the combined data from all appends in the conflation window, with the operation metadata from the most recent append.
+The append messages must all have the same data type (e.g. all strings or all binary) in order to be concatenated correctly.
+
+### Update and delete conflation
+
+When an update or delete occurs, it supersedes all previous operations for that message in the time window.
+If additional appends follow the update or delete within the same window, Ably combines them: subscribers receive the full message content including those appends, rather than receiving the update followed by separate append operations.
+
+Conversely, if an update or delete arrives after appends in the conflation window, the update or delete wins and discards the pending appends.
+
+<Aside data-type='note'>
+The exact conflation behavior depends on timing and batching intervals, but subscribers always receive a consistent final state that matches what a history query or [getMessage()](/docs/messages/updates-deletes#get) request returns.
+</Aside>
+
 ## Get the latest version of a message <a id="get"/>
 
 To retrieve the most recent version of a specific message, use the `getMessage()` method on a REST channel. You can pass either the message's serial identifier as a string, or a message object with a `serial` property.