Just as an update... I finally flew my outbound segment for my DL531/mileage upgrade of a DL/AF W flight. I had approx a 30 minute delay at JFK while they reissued my ticket again at the AF counter - when the flight went to gate control I was completely removed from the flight. Before then, it was showing up properly, and the ticket was correctly showing WHWLSUS/D531 for the fare code. Buyer beware to leave extra time...