Originally Posted by
GYEWorldTraveler
I'm thinking if its a DL fare Y, B, M, H, Q, K, L, U, T, E then you would be eligible for an upgrade but if it is another airlines fare (like AF W class or something like that) that you would not be eligible. You can always call and ask them to try and put you on the UG list though. I wonder if they can change the flight to the Delta coded number in the reservation and maybe that would help? It is worth a call to see.
If anyone does this, or tries to do this, I'd really like them to report the result here. Very curious as AF codeshare flights on a certain itinerary mostly on DL metal is showing $100 cheaper than DL booked itinerary with the exact same flights.