I'm debating booking the free dining bounceback offer during my next stay. But I want to make sure I know what I am doing first. 
There will be people who be at WDW for less time than the rest of the group. Some of us will be doing 7 nights and some 4 nights. When I book, I obviously want the rooms for the 7 nights. So can I book the free dining bounceback for 7 nights but with 4 day tickets, or does everyone have to have 7 day tickets?

There will be people who be at WDW for less time than the rest of the group. Some of us will be doing 7 nights and some 4 nights. When I book, I obviously want the rooms for the 7 nights. So can I book the free dining bounceback for 7 nights but with 4 day tickets, or does everyone have to have 7 day tickets?