I had a ticket to fly to ATL today, but no longer needed to go as of late last night. (It broke my heart though, as I had been upgraded both ways!) When I went to DL.com to cancel the ticket I noticed that my original flight had just been cancelled. I was re-routed on the next flight in full F, rather than V. However, I still didn't need to make the trip (sob- oh the lost miles!). I called DL and received a FULL refund of my U fare. Sometimes cancellations are a good thing!