I know a lot of people have wanted to change their arrival date and have been put on wait lists. how likely is it that they will get it? I guess it depends on the other people.. but I have an internship and they said they're flexible with end dates but the last event is 10 days after my arrival and I kind of want to be there if I can. otherwise I would miss two events. So is it possible to change it if you have a reason like that?