Hi there, Sheri!
I see that you're a planner after my own heart! I love it!
The calendar is typically posted 6 months or so in advance. You'll be able to see the Park hours and entertainment scheduled during your vacation in the
calendar section of the Walt Disney World website. Since your trip is at the beginning of May, you should be able to view the Park hours toward the end of October. You'll see a little calendar icon that turns blue when you hover your mouse over it. If you click on that, a pop-up calendar will appear where you can arrow over to your vacation dates. You can tell if the calendar is available for your date because the actual day will be blue and clickable when hours have been posted.
Advanced Dining Reservations can be made up to 180 days in advance either
online or by calling 407.WDW.DINE [939.3463]. If you are staying in a Walt Disney World owned Resort hotel, you are able to make your dining reservations up to 10 days into your vacation, giving you a jump on those staying off property.
I hope this helps, Sheri! Thanks for stopping by the Moms Panel with your question and please let us know if you have any other questions we can help with!
Wishing you Pixie Dusted vacation planning!
~Jackie