I just did this so I found out first hand.
We are staying RPH and originally booked at 234.82 per night, 1 night deposit charged to CC. When they announced APH rate, I called. They gave me the new rate of 154.45(tax included).
Now the catch, they do recharge another whole nights stay and ten refund the first deposit you left. Unlike Disney they do not adjust and leave a credit against the room.
I found this out by calling accounting to verify ny CC was credited after I saw the secodn deposit charge.