Ok, hopefully this makes it to you quickly enough. What agreement do you have with B6 and UA? If you're trying to use a ZED-low ticket and you have a ZED-medium agreement with UA, you're out of luck. If you're using an equal or better ticket, you should be ok. You just won't get the difference back if you use a better ticket than you need.
Now, the more important part is to talk the gate agent into allowing this. Check your paper ticket. Does it say "VALID ALL ZED CARRIERS" anywhere on the ticket? That should help. We still take paper tickets, just not for all airlines. If worse comes to worst, which airline do you work for? I remember looking at the page for one airline, and it mentioned that it was ok to take those tickets as long as it's equal or better level. Tell them to look through GG PASS OA, with OA being your airline (LH, AA, what have you). There should be a mention of it somewhere. They should know what that means, GG is the helpfile in our reservations system and is pretty well-known by any gate agent.
Of course, don't drain the time of the gate agents, either.
Edit: Also, I removed your other post. Hopefully this takes care of you. We really want to avoid duplicate threads whereever possible.
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