And remember, this is a live ball foul so DON'T blow the whistle (unless he already crossed the neutral zone, then it's a Dead Ball procedure penalty)
What's a "procedure penalty"? There is no such thing in high school football.
If the motion forward simulates the snap, then it's a dead ball foul for a false start. If it's a simple turning upfield too early, it's a live ball Illegal Motion foul. If he crosses the line, it would be an encroachment foul, also killing the play.