I usually recommend that parents try to fly in the mornings when possible. Flights are more likely to be on time and children are in better humor.

I cringe every time someone says to fly when the child naps. As a Flight Attendant, I saw this go wrong so many times. First, if you have a delay, you're sure to have a meltdown. Also, some children get so overstimulated in airports that they don't settle down on the plane.

But having said that, I hate to recommend the 6:30 flight but we have done really insanely early flights and every time, it's gone really smoothly. My children are very active (the oldest and youngest especially) but no sensory disorders or hyperactivity. They're usually excited to be going and don't mind being woken up. Once they go through the whole dance of check-in, security, boarding, etc. by the time they get on board, they crash out (bad wording when talking about flying??)

I have worked similar routes. Orlando traffic tends to be a lot of children and mostly tourists. Early December is usually a quiet time since the Christmas vacations are coming up and most parents wait till the kids are out of school to go. Of course, there could be a conference or a to-die-for promotion going on so don't revel in too many empty-flight fantasies! But it's not unreasonable and you might want to "risk" the 10:30, just for your sanity's sake.

Since your child has a diagnosed condition, I assume that you have discussed this trip with his doctor (or plan to). Be sure to bring up the subject of drugs. Don't give him anything he hasn't taken on the ground first so you might want to bring this up, and organize it well ahead of time.

About the room being ready, officially it's 4pm but there's a good chance you'll be able to get in before that time. Once your room is cleaned, they'll give you the key. In any case, you can leave your bags and check-in right away.