Just checked the rulebook.
The only situations where refs have the leeway to change calls made on the floor is for the cylinder rule and the hook-and-hold rule.
Both allow refs to re-adjudicate the entire play during replay, which is crazy to me.
"d. Fouls
1. After a call has been made, determine if a flagrant personal foul or a flagrant 2 contact technical foul or a contact dead ball technical foul occurred. When it is determined that a flagrant personal or flagrant 2 contact technical foul did not occur, but a contact dead ball technical foul or common foul did occur, those fouls shall be penalized accordingly. However, no other infractions may be penalized. When the review discloses, by indisputable evidence, that there was no contact, the foul call shall be reversed with no foul charged.
a. When there is a foul called for contact, the officials, with a plausible reason, may review the severity of that foul during the dead-ball period following the call. When the ball becomes live, there shall be no review of the made call.
b. When there is a foul called for swinging of the elbows involving the cylinder rule or a hook and hold play, the officials may review the play and adjudicate all penalties by removing fouls, assessing fouls against any player or concluding that no foul(s) occurred."