I say leave it open with no plans, and when the day comes, there will most likely be something that you and your group wanted to do again, or a park that you just really enjoyed more than usual that you would want to visit again.
That's why I like staying at the Yacht Club, I can just walk back from Epcot and catch a taxi.I have had late flights before and spent the morning at one of the parks. Actually few times. However, there were two occasions that caused worry. Once when went to the bus stop at the park there was no bus and we waited quite a while. We were the only ones there. Luckily a CM walked by and said something like "waiting for a bus?". I said yeah and I have a plane to catch. He walked on further and I noticed him making a phone call or what ever they have. A couple of minutes later a bus comes up and the driver says "looking for a ride huh" with a huge smile. So I believe the person walking by made the call. The second time we got to the bus at the park and there were few people already on. But the driver just sat there. We sat for about 5 minutes and I began looking at my watch. Finally he started the bus and took us back to the resort. Now, I don't try to get a late flight and plan on spending the day at the resort before our flight. I would give yourself plenty of time on your return from the park on the last day.
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