Hi, Ashley! I would say you should be okay between the
Bibbidi Bobbidi Boutique and breakfast. I always say allow at least 45 minutes to transform your pint sized princess, and with just over an hour, you should be okay.
Breakfast at 9:20 is going to take about an hour, so expect to be leaving
Cinderella's Royal Table just after 10 o'clock. You may be able to eat more quickly than that, but this allows time to make sure you see all of the characters before you leave. 11:10 sounds a little bit close to me for lunch - almost like you'll be getting up from the breakfast table and having to head right to
Be Our Guest. My kids would be upset that so much of their Magic Kingdom time was being taken up by dining reservations!
If you can snag a later reservation, I would go that route. If you can't, but you really want the experience, go for lunch and just plan to eat a lighter meal or even just a dessert. It's so amazingly themed, you don't want to miss it if you don't have to!
Have a great trip!