So we see the problem. U hustles, gets the ball, spots it and sees 11 in front of him after he's got it spotted. He's back ready for the snap, and notes that the snap goes off with the snapper clearly still moving and drops a flag. He's got an illegal snap since the center was still moving, the BJ has his flag for B having 12 on the field. Can we just "wash" the play, warn A and have a "do-over" or should we call offsetting penalties, remind A of the substitution rules, and move on?
Also, doesn't the wing official on the team A side of the ball play a role in the sub issue here?
You will not have offsetting. Its a question of timing. If you (the crew) determine that A had met their obligation to allow Team B to complete their match-up substitutions, and Team B was simply taking too long, thus they had 12 players on the field for more than the maximum 3 seconds before attempting to leave, then you have a dead-ball illegal substitution (before there could be a snap). So, the snapper's action is moot - nothing. Shut the play down and penalize B.
However, if you determine that B was reacting in a timely manner to A's substitutions, and the snapper was trying to put B at a disadvantage by snapping before B had completed their substitutions, then you would either have a false start for moving early (when he was moving to adjust his position to be able to snap the ball), or, if you deem the snapper's actions as being legal movement (not a false start), then you'd have a "do-over." Shut the play down, let everybody complete their subs, set the play clock to 25, warn Team A that the next such attempt to put the defense at a disadvantage would be an unsportsmanlike conduct foul, and declare the ball ready for play.
The opposing actions are mutually exclusive, i.e., if you have one as an infraction of the rules, then you can't have the other (by rule). So, no way to be offsetting.
