Hi Beth!
Thanks for stopping by the Disney Parks Moms Panel. Since the
Flag Retreat is held at 5:00 PM on Main Street U.S.A. not far from
Tony's Town Square, you should have no problem making your 5:30 PM Advanced Dining Reservation. If, however, you are late, simply check in with the Cast Member out front as you normally would. Inform her that you are late and, depending on the crowd that evening and exactly how late you are, she will let you know if your party can still be seated on your original reservation. I do think you will be just fine, though, as long as you go directly from the Flag Retreat to dinner.
We love helping Guests plan their
Walt Disney World vacations so please come back if there's anything else we can do for you.
Have a wonderfully magical day!
-Nancy-