Route: RDU-LGA-YUL
Fare: F

What Happened: RDU-LGA delayed so that I would have missed LGA-YUL. Called DM line for help and was rerouted RDU-ATL-YUL, but RDU-YUL was full in F, so I was assigned a C+ (middle) seat.

Compensation: Phone agent offered (without prompting) $200 voucher + refund of fare difference between F and W for that segment. Not bad since I ended up in YUL only 30 mins after I would have via LGA.