I usually do those times for ADRs and its usually pretty busy but it depends on a few variables such as what restaurant you are going to. I find Captain's Grille, Marrakesh and Raglan Road (During the day not at night) tend to be pretty quiet.
Whereas Le Cellier, Crystal Palace and Chef Mickeys would be hectic all the time.
But if you have ADRs don't fret as you have a guaranteed seat and don't have to fight to get a walk-up spot.
Im going during
Free Dining soon so I hope you have a magical trip