There is one hitch that has caught me now and then, when I was re-using a flight plan with which I had previously gotten a briefing and filed with iFly. IF I didn't make the flight and also didn't cancel that flight plan, iFly wouldn't let me file it again. That seems logical enough now--except that I felt it should have timed out and was puzzled when I tried to file later and iFly popped up a cryptic message, something like "it didn't work." Eventually I realized that I had to cancel the plan manually before iFly would let me file again. I just tried it a few minutes ago and it didn't seem as cryptic as a few months ago, so maybe it was fixed. Or I got more sensible. Whatever, I think iFly should automatically cancel a filed plan a day or so after the original planned departure. (Is this just whining about something I ought to know naturally?)