Originally Posted by
jsloan
You might be able to get UA to waive the change fee -- call and ask; you'll likely have better luck if it's ticketed as UA codes than LH codes -- but if you're trying to up-fare a single segment out of a longer itinerary, you're likely to run into an extremely high fare difference.
The flight does have UA codes but the 1K agent told me I could not buyup through UA. She did share with me that had heard from other pax that they have been successful calling LH.