We need a mechanism to gracefully handle cases when an NP-simulated object changes net roles from autonomous to simulated, and vice versa. The most common case happens when a client player possesses a pawn, then unpossesses it and possesses a different pawn.
This should include a process by which the server and client come to agreement about which sim frame the change occurred, and that they transfer responsibility for producing input between themselves at that frame boundary. It is OK if there is a window where both client and server are producing input, as long as the bookkeeping is corrected once the frame is determined.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-148945 in the post.