We had an odd play that I realized after the game we signaled incorrectly (and I believe enforced wrong as well). 1st and 10, A7 goes to hand off the ball, realized the RB is not where he should be an then quickly throws a pass to A83, which falls incomplete. A83, not thinking it was going to be involved in the play had failed to remove his mouth guard from his facemask and put it in his mouth -- which is failure to wear required equipment during the down. (He had been previously warned about this as well -- he had a habit for not putting his mouthpiece in if he wasn't going to be involved in the first play of a series off the bench).
We enforced the five yard penalty, and replayed 1st and 15. However, since it was during the down (and not killed before the play) this is a violation of 9-9 and not 3-6-2d, and this should have been a succeeding spot foul (which wouldn't have changed the yardline of the next play), but this means it should have been 2nd down, correct? There's no case play that explicitly states this, but the succeeding spot enforcement says this has to be true.
Furthermore, the appropriate signal is listed as S27-23 for violating 9-9 (The WH only gave S23 in our game). Since it is only a 5 yard penalty, I assume S27 is used under the context of a noncontact foul, not a USC, which means you get to explain to the coach of B why it was only 5 (not 15) yards and why that foul wouldn't count towards disqualification. There are no other fouls that use S27 that would not be 15 yard penalties and/or would not count towards disqualification, therefore this seems like it would be a very confusing (albeit unusual) signal. There are many other "non contact" fouls that we don't use S27 for, is there a reason why this one still includes it?