Quick kick play

[Opie]

Fed.
By definition, A1 is a kicker and is afforded protection. If B is not reasonably certain a kick will be made, B is granted some leeway, which he would not have is A is in scrimmage kick formation.
If B could have stopped, you have roughing. If he is already committed to his charge, no roughing. Depending on one's definition of slobberknocking, you could have a PF.
This is a judgement call that should be called very similarly to a roughing the passer call.