There are multiple bookings available for cash on the date I selected, but when I try using my rewards, these availabilities disappear with "Unfortunately, no points redemption rooms are available for the dates you selected.".
Is there anyway to override this for Elite members?
There are no black out dates for reward nights. However, they are capacity controlled. That means that fewer nights are available during high season etc. When I have needed award stays and they were not available, the Plat line has called to try to get them. Success has been variable. The less nights you need the better as well as fewer the rooms. If you need one room for one night, you might get lucky. If you are trying to get 4 rooms for a week, you might have trouble. Good luck!