Here's what I did for a test...We had a 5/12-5/18 reservation at the campground. Yesterday I shortened it to 5/14-5/18 to see what would happen. Granted, I made these FP+s with that weird early window that some of us are able to access..but my husband just got the warning in his email. The "If action is not taken to restore your eligibility, these FP+ selections are subject to cancellation on 3/2/2019." I will report back if/when they actually get cancelled.