We are on enchanted now and i will say, there is a lot of shade in the Sanctuary, but im sure you will find some sun, however, if you are looking for a chair directly in the sun, i dont think you will have a hard time in the regular areas. There are a lot of chairs especially on the deck above the main pool.
Also we are in a suite and although i dont know if that gives us priority, but we put our name on the waiting list that was almost 2 pages long when we boarded and a little before 5, we got a call that we could have any days we wanted.