Maybe, maybe not. I am currently holding two award tickets for travel in early September. Issued on DL (006) ticket stock (SkyMiles awards), the itinerary was originally an all-AS itinerary, but due to several schedule changes is now DL outbound and AS return. I have the DL and AS PNRs. I also have the two DL ticket numbers of the re-issued tickets with the latest itinerary. When I spoke with AS recently, they can see the reservation as well as the ticket numbers, but told me that "DL hasn't sent the tickets over yet". I'm not sure what that means, but it suggests that there is something else AS should have other than the reservation and ticket numbers. Since I don't expect any additional schedule changes, I plan on calling AS again soon to attempt to clarify and, if necessary, call DL to see what can be done. I don't want to show-up for my return flight and find I'm not boarding because of a DL screw-up.

I have had problems before with mixed carrier itineraries (not DL, but with CO and NW), and try to avoid them if possible.