Pls confirm - s2s question

As I understand it - based on what I’ve read about xmpp:

ClientA joins a room hosted on the remote ServerB and the room history is downloaded to ClientA.

But it doesn’t go directly to ClientA, instead ServerA receives the msgs from ServerB and then passes them along to ClientA.

So the msgs leave ServerB in order but there is nothing on ServerA to retain/respect the order from ServerB when ServerA passes the msgs to ClientA.

Does ServerA store the msgs anywhere (ofMessageArchive?)

Would Connection Manager be able to throttle the threads avail between the servers in order to force the msgs to stay in order?

TIA