Originally Posted by
sabbasolo
They don't apply LH requires paper GPU's, one per flight, so even if they were both LH sectors, and if you had been upgraded with a paper GPU, it wouldn't be valid for the second sector from FRA->SOF.
Many thanks. I also learned that LH doesn't allow upgrades on W fares as UA does, so it wouldn't have worked regardless. Fortunately the upgraded legs are much longer.