It should be fine or better. We had an 11:20 ADR for breakfast last year; bfast ends at 11:30. The buffet was full and hot and we took our time eating and having fun. We ate well, had fantastic character interaction and just fun, fun, fun at Chef Mickey's! Go and plan to simply enjoy it. Besides you're at WDW CM's has an extensive sundae bar you can have dessert for dinner if you want at Disney!