hmm technically she was correct, as you did not check in for your new flight, even though you got a conf upgrade and seat assignment. If you would of done a online checkin, then she could of checked you in and reprinted a BP. I believe the cutoff time is 30min for checkin, then it goes gate control. Best just check in online even if you cannot print, at least that way you are checked in.

2nd part, I understand the frustration when flights cancel, but its not better with any other airline. They will do anything from having to put you on another company. You were right on that part. Its listed in the Contract of Carriage