Chex,

I have been told that it's one or the other. Definitely DON'T call the CP or other res line. They will make the change, but also quickly move you back to coach.

I've read that some people have had luck doing this at the ticket counter. But it's the RETURN flight that concerns me. If I've been upgraded, I may well be re-seated in coach. If I haven't cleared, or want to stand by, I'm at the bottom of the list. Additionally, since CP's don't have E-upgrades, I would have to pay for each 500 mile upgrade I needed. Ick.

I agree that I'd love to hear from people successful with doing this - when and where you made the mileage change - and from anyone who HASN'T been successful - moved back to Y, etc.

I posted a similar thread that got a few responses, but maybe more people will post here.

http://www.flyertalk.com/forum/Forum51/HTML/005699.html