Can 500-mile UG certificates be used internationally? If there is no C availability at the time your window opens, is there a waitlist that will definitely clear if a seat is available in the UG cabin?
Regarding mileage UGs, do you have to pay the co-pay if you go on the waitlist? Or only when it actually clears?
Do UGs have to be re-ticketed by a phone agent like they do on DL?
Thanks!