There is no such thing as a good night time hour. We went at 9 pm and had a 90 minute wait. It stayed full the whole evening.
The only time we'ver found it not crowded is mid afternoon--like 3-4:30. Lunch usually has more than an hour wait, ditto for dinner.
When we stay at Beach Club, we send one person down to sign us on to the waiting list, then the rest come over 30-45 minutes later. If I check in at the podium and they say less than 30, I can always phone the rest of the gang!