I understand if a flight is running late the agent will sometimes not come on to move people up. But honestly the simpler way that most US gate agents do is tell the FA's on the flight and they ask for the person to ring their flight attendant call button.

Then they move up with the one FA's help. This way the other FA's can close up the doors, etc.

PSU Lion: Terrible experience, sorry to hear it. I assume you wrote to USAirways Customer Affairs? The two times I've wrote them I've gotten what I asked for -- did you ask for something specific?