12 men on the field - deadball?

[Mike Simonds]

We tell our wing men to step up towards the numbers if a sub is running off. Give them a chance to get off the field or at least behind your field of vision so you won't have to penalize something that does not affect the play or deceive the opponents.

Over here the BJ (5 man) or the FJ & SJ (6 man), counts the defense. Better to get an early whistle for illegal sub, dead ball foul.

If you are close to the snap, better to make it a live ball foul. And you guys are correct, A can take the point and enforce the penalty against B on the kick-off.