I don't know why people are getting anxious about it being "crowded" during September, or when they are offering
Free Dining.
Once again, a Disney CM friend of mine told me that during their summer months (June-August), they typically have 80,000 people, whereas in September, they only have 18,000. And I, too, was there last year and it was the so uncrowded, it was SCARY...I had never seen it so light on crowds, and that was when they had Free Dining. The longest wait we had was a half hour for Pirates of the Caribbean, everything else was either a 5-minute wait or walk-on.
And as far as booking your vacation THE MINUTE they release Free Dining, I really don't see how that's necessary, unless there are is a hugely significant number of people now who are waiting to do this. We didn't book our September vacation last year until late June for the POFQ, and we still got Free Dining.
The only thing, once again, is making your reservations at table-service restaurants BEFORE you go, up to the day you book your trip, because the popular restaurants (Cinderella's Royal Table, O'hana, etc) book quickly.