Well....since you are going at a busier time, my advice is to go to your chosen park as soon as it opens. The parks really get crowded by 11 am. Lots of times the water parks will close due to capacity around this time, too. The water parks usually open back in the late afternoon (people are tired and leave).
We always leave the park, take a midday break at the resort and return to a park around 4 pm.