Yes, it is expected and it is ok.
I just wanted to show you what caused the problem of order of events at client.

- new Subscription("COMMAND", "Abbruzzo", cellList);
- we return Snapshot.
- _listener.OnEndSnapshot(Abbruzzo);
- we updates ...

we added update.Add("command", "ADD");
_listener.OnEvent(Abbruzzo, Filetto, false); // FALSE is WRONG !!!

- we refresh the browser.
- we get wrong order of events !

But after we set:
_listener.OnEvent(Abbruzzo, Filetto, true);

everything is ok !

regards!