Originally Posted by
platbrownguy
If you have an expertflyer subscription it's not hard to use the BXP1s. Just set alerts, search around, etc. I've had no trouble booking JFK-LAX/SFO flights (either in Y, to confirm into C; or in biz, to confirm into A) that I could confirm the upgrade on at the time of booking.
Of course, simply trying to use them on existing reservations is a fool's errand.
How do you confirm them at time of booking? Do you have to book on the phone for that to work?