If you're trying to suggest that 56 picks up his hand *while* 80 is moving back, then I'd call that a false start. Until 80 is clearly "a back", he's the end -- which means 56 isn't.
If 80 shifts back, gets set for a second, *and then* 56 picks up his hand -- well, he's the end at that point, so it's allowed.
The idea that all four players are moving as a designed shift is unlikely as well. It just seems unnecessarily complex with no obvious goal. Chances are, one of those players was not supposed to move and it will be obviously a false start when you see it live.