I thought of something that might be helpful. When you register (all but Royal guests) will get a towel card. You can use the card to exchange for a clean beach towel. There are 2 towel huts; one at each the main pool. Some of the beach bars, like La Jarra on Kantenah and The Rocos at the salt water pool get towels mid morning. Be sure you don’t lose your towel or card as you will need to have a towel card to leave the resort or will be charged.
If it rains many people may be turning in wet towels for dry ones at the same time thus the towel huts may run out. The resort has its own laundry and is constantly supplying clean beach towels but in the event of wet weather, turn your wet towels in early on for dry towels or you may have to wait for a fresh batch