I bet the car was warm from the service/inspection, it makes a huge difference on mpg. I take a break half way through my 130 mile commute, the computer resets and I often get 42mpg for the second half of the journey.
My 2014 250 is averaging 37.5mpg on trips to work, I can get 40mpg if I'm really careful but it's not worth it. Today I did the 260 mile trip with half a tank :)