I have had the service shifter issue on my 2015 Sport three times, and took the vehicle in all three times. The first time, the dealer did a flash upgrade. The second time, the vehicle started with service shifter, then switched to service transmission and went into limp mode. The dealer then found a stuck open valve and replaced it. Both of these visits were covered under the powertrain warranty.
My vehicle is currently back in the dealership for three days now. The first day (with appointment) and description, they said they could not address the problem because the service shifter lights did not come on for them. The second day after showing them pictures of when it happened they said they found some replacement parts they were going to bring in from Atlanta at a cost of 170-180 dollars + labor, and that it was not covered under the powertrain warranty. I guess I am wondering why the first two visits were covered and I received a loaner vehicle, but now they are charging me for parts and labor which I do not know will fix the problem, and I have not been offered a loaner vehicle. It has been very frustrating and I still do not have a car.