Hi, Megan!
Thanks so much for stopping back by with this great question! I'm so sorry to hear about your experience last year with the late bus. I will say that your timing was spot-on though. I have a couple of suggestions to try to ensure a smoother morning and a more leisurely stroll down Main Street U.S.A.
Arriving at the main entrance of Magic Kingdom Park about 30-minutes prior to your
Advanced Dining Reservation is exactly what is recommended for early admission into the Park. I would plan on being out at your Resort hotel's bus depot by no later than 7:00 a.m., I might even arrive by 6:45 a.m. just to give a few extra minutes. You should see a Cast Member there with a clipboard and they will more-than-likely ask you where you're headed. These Cast Members are there to help make sure you get to your intended destination in plenty of time. If, by chance, you don't see a Cast Member, just pop back into the lobby and let the concierge know that you're heading to Magic Kingdom Park for an early breakfast reservation and you'd like them to check and see when the next bus will be arriving. They should be able to find that out for you and you'll be on your way before you know it!
Strolling down a practically empty Main Street U.S.A. in the very early hours of the morning is one of my most favorite things to do at Walt Disney World and I sure hope that your early morning is magical in every way!
Have a Pixie Dusted vacation!
~Jackie