Originally Posted by
MSPeconomist
Could O be relevant when married segments apply with the DL segments using OY? I'm thinking of my own ticket here.
EF does specify that Z is for GUC upgrades on KL while O is for some other kind of upgrades, which may mean mileage upgrades.
My more general observation on married segments is that when I was booking, I saw (not for my dates, but for other dates) lots of NYC-AMS-CPT options where the routings with KL-operated JFK-AMS flights showed 0 Z on both sectors, but the routings with DL-operated JFK/EWR-AMS flights showed available Z space on both sectors. But it's not clear if that's "real" space since you're not actually booking Z space on the DL sector, you're booking OY space, but does the married segment logic still create Z availability on the KL sector? And if it doesn't, does Z availability for an independent AMS-CPT trip govern upgrade availability on that sector?