Always an expanded neutral zone?

[kentref]

NFHS rules question re: 2-27-2 that states, "The neutral zone may be expanded following the snap up to a maximum of 2 yards behind the defensive line of scrimmage, in the field of play, during any scrimmage down."

Since the definition says, "may be expanded..." my question is: Are there any situations where the neutral zone would not be expanded during a scrimmage play, (other than it can't be expanded into the end zone).
For example, I've noticed officials calling illegal forward passes by A when, on an option play, the QB is slightly behind the back he's pitching the ball to and both are within the "expanded neutral zone." So in a forward passing situation like this where does the foul occur? When the QB is beyond the defensive line of scrimmage, or when the QB is beyond the "expanded neutral zone" (up to 2 yards behind the defensive line of scrimmage)?