Depends on the resort. For a number of them, the pools are open 24 hours a day, although some only go to 10 or 11. However any slides are closed when the lifeguard leaves which at most places is 7 or 8 although at Stormalong Bay for YC/BC/BCV I think they are there until 10 (when that pool closes), and the bars also usually close about the time the lifeguards leave.