That has nothing to do with the rule. It states the team shall not be in continuous control of the ball in the back court for 10 seconds. Once the ball is in the air and over the half line it isn't a violation. It even says refs should go to the shot clock to verify. It was on 21 when the ball was no longer in continuous possession in the backcourt.It wasn’t POSSESSED over half court until the shot clock hit 20. The ball being in the air before that is not sufficient.