I think Disney will work with people who have obvious issues with flights, even if you have to get a supervisor to do it. Since you book your vacation so much further in advance than flights can be made. But will limit that as well if they see people abusing it.
I book via a disney vacation specialist, and was told that there will be an issue in regards to changing my ressie if/when FD comes out. SO we just went ahead and cancelled the whole trip and anxiously awaiting the Visa FD days now to rebook!! which is prolly gonna be better for me anyways considering i had booked for last week of Oct, andschool schedule was just released and if we go mid month instead my kids will only miss 4 days of school instead of 5, and I wont have to attempt to drive 13 hours straight, and arriving at disney totally exhausted from being up all night driving. Since we will be able to leave Friday morning and get to florida friday night and stay off site 1 night, and be well rested for our first day!!!