When is a sub a sub?

[Andy]

Well, I do it just the way you do. I do not recognize and signal the substitution until the head coach requests it and/or a substitute enters the sub zone.

I don't have the book (NFHS) handy here at work, but I believe that there is not a substitution request until one of those things happens. If I signal the substitution prematurely and the player realizes she is not supposed to go into the game at that point, I have to assess a UD for withdrawing a sub request. If I wait until the request is valid, by the actions of the player or coach, now it's on them if the request is withdrawn.

I have not noticed the issue you have with a hesitation before entering the sub zone, I seem to have more issues with getting teams to send multiple subs all up to the line at the same time.