Join Date: Apr 2009
Location: Bye Delta
Programs: AA EXP, UA Silver, HH Diamond, IHG Plat, Hyatt Plat, Marriott Titanium, Nat'l EE, Avis PC, Hertz PC
Posts: 16,632
I don't think there will be an issue with the mileage posting. We have seen this pop up on the forum from time to time. Remember that even with direct flights, you can get credit for the stop if you book multi-city. For example:
DL 3156 IMT-DTW (1 stop)
would get credit for IMT-DTW
DL 3156 IMT-ESC (Nonstop)
DL 3156 ESC-DTW (Nonstop)
would get credit for both segments
Since you can't book a trip from DTW-DTW, my belief is you will already have DTW-XXX and XXX-DTW listed separately on your itinerary and you will get credit for both without a problem.