Hi, Jasmine!
I think you may have booked your schedule a bit tight! With an 11am - noon FastPass+ for
Big Thunder Mountain Railroad, you are really going to have to hustle to make way back to Main St. USA for your 11:15am
Plaza Restaurant reservation. So what happens if you are late? Technically, I guess you can be denied seating. However, you will most likely just have to wait a bit longer for a table to become available.
When planning your times, remember that your
FastPass+ window is when you can enter the attraction FastPass+ queue, not board the ride. (Most times, you can enter the line 5 minutes prior to your FastPass+ time.) You may still have to wait several minutes or longer to board your train, allow ride time, exit the ride, and make the 8-10 minute walk over to the restaurant. I think the soonest you would be at your reservation would realistically be 11:30/11:45am.
If possible, try moving your Big Thunder Mountain Railroad FastPass+ time to add some extra time between your FastPass+ and your reservation time. Even if late, show up for your dining reservation because there is a $10 per person "no show" fee that I would not want you to incur!
It's up to you if you want to update your FastPass+ time, but I know I do not like to rush, especially on vacation. You will have to decide if you want to chance the late arrival at The Plaza Restaurant, or just move a few things around to reduce stress and rushing. Good luck deciding, and once you do get to your lunch, make sure to order one of their yummy milkshakes!
Cathy