Hi and welcome!
If you're going in April, why not book now? Also, if you're thinking of having any sit-down meals, you can book them now as well.
I realize how silly that sounds. But meals at the WDW restaurants can be booked 180 days before the start of your trip, and many are. The earlier you book, the more options you'll have.
Where are you planning to stay? If you haven't yet decided, why not take a look at the fact sheets and slide shows at
www.allears.net.
Planning a Disney vacation is so very much fun!