IS 4 months ahead too late....it depends, and probably not. If you are scheduling 12 people at CRT, it may well be too late. For 4 people at most other places, you'll probably get what you want.
We are travelling in May and I called yesterday and added some ADRs. No problem--got our first choice restaurant and within 30 minutes of our preferred time. I'd done the others about 45 days before travelling.
To plan, I list the restaurants DD wanted to use. I'd printed off the menus for most that I considered acceptable, then let her write "yes" or "no" on each one. She then chose from the "yes" to get the right number. I then made a sheet listing which parks had Extra Magic Hours for each of our days, and decide which restaurants will work with the parks we plan to visit.
Before I call, I make a list of my "preferred" requests, and off to the side in another color, I list some alternatives for that day. I've never had to go to my alternatives list, but at least I'm ready when I make the phone call.
All this planning is lovely. However, since DD is now a teen...the best laid plans are subject to change. She does like the evening EMH, so those usually stick for park choices.
