Originally Posted by
hhdl
Ah, it's because DL can only clear an upgrade to Y+ if the flight is DL-marketed or if it's within 24 hours of departure (at which point FB elites are unlikely to clear). Of course, what's a benefit to the Platinum (and maybe even Gold?) is a detriment to those who want UXP.
One wonders if it's possible to display both codes.
Doesn't really make sense. Why only DL non-stop itins and not also 100% DL metal itins which involve connections like the following (which are booked as AF/KL codeshares) --
https://www.flyertalk.com/forum/37659901-post5.html
Note with the DL coding you are also booking DL fares (not really a big deal as the fare filings are coordinated) and using DL class inventory availability on flights. I have a sneaking suspicion they don't want US origin pax bypassing DL RM management systems and inventory management on the hub-hostage non-stop flights by booking as AF/KL codeshares.