Boarding YVR to DEN on Friday. I approach the GA and observe the agent at the desk being verbally dressed down by a passenger. He drops the 1K bomb and stomps off ahead of me and onto the plane. Well, suddenly my name is paged by the same desk agent who then asks if I would mind swapping my 12C (A319) for 9C. While I hesitate to answer, the GA fills me in on the story. This passenger evidently upgraded himself to FC and was given a seat in the first row. He was complaining to her that he NEVER sits in the first row and wants another seat in an otherwise full first class cabin (...?, there are only two rows in 1st anyway on a A319). So anyway, she offers to put him back in E+, he agrees but says he wants 12C since he (incorrectly) states that it was his original seat (I'd had 12C for weeks). He gets PO'd rants that he is a 1K and stomps off.

After the GA has recounted his rude behaviour, I apologize for a fellow frequent fliers rudeness and next thing I know she op up's me to his now vacant first row seat. Pretty sweet deal. I did warn a crew member that 9C was likely to be grumpy, after her walk through, she concurred.