We will be there the week of 3/20-3/26. a friend came 2 years ago and gave me her itinerary and it says park hours are 9-9 all week but now it shows parks closing at 7 every nite but Saturday(Mardi Gras)-anyone remember from last year?
It would be nice if the theme park industry had set hours like Wal-Mart, but they don't. There operating times seem to be more in touch with the way the tourists book their vacations. If the economy is bad and no one is traveling then they will close early, if it is good and they expect a lot of visitors then they will stay open later. Unless of course you look at amusement parks like Six Flags, they buck the system because they are only open during specific times in the year and build the highs and lows into their operating budget.
During some of our trips to Florida, the opening and closing times have changed even down to the day without any prior notification. For example, we arrived at the Magic Kingdom in Walt Disney World for their stated opening time of 9AM, and found out that the gates had actually opened at 8AM, and no this was not due to an early entry day as they schedule for certain parks on certain days.
All of that said, your best advice is to research the most current hours on their website and read about the rides offered and list them in priority and hit the ground running, depending on your expectations of what you hope to accomplish in 1 days time.