I'm still amazed that Ime bothered to use the challenge with 3 seconds left to switch a foul from Rob to J Rich when Rob wasn't even in foul trouble.
In my understanding, you don't challenge a call to go from x to y. You challenge the call in general. Refs decide what happens next.
So in short; maybe we went "that wasn't a foul" and then the refs were like, "you're right, it wasn't, but that JRich stuff was".
I thought on replay refs were only supposed to check the call made, not make a new call.
From what I've seen; they assess the call, and then decide on what the play should've been.
In this case, it was a foul by someone else anyway, so remains "similar", hence the confusing wording of "call is overturned".
In other cases, they let a team have the ball.
In other cases again, they call a jump ball because no team had possession.