I was watching the Baylor Oklahoma game, where Baylor kicked a FG as time expired of the 1st half. A25 was down, in bounds, short of a first down with 13 seconds left on the GC. A brings out the FG team, got everyone set ready for the snap, and the umpire backed away with 3 seconds to play. The ball was snapped at 2 seconds, and the FG was good.
In this case, B chose not to substitute. However, if B did subtitute, I just don't see how B would be able to complete the substitution, and line up in that short time period. Surely, taking an additional 3 seconds longer to decide what to do, substitute, and line up than what it took A to do so should still be considered as attempting to complete a substitution promptly, and thus with the running clock, the GC would reach 0:00 before it can be snapped even though A is ready to go.
Is there any special handling or expectations for team B on how quickly they complete there substitution in this situation?