I noticed the same thing. I just got my 2017 a couple of weeks ago. Set up my wife as driver 1 and me as driver 2. We both got in the car with both fobs and the seats immediately shoved my under the dash. (she is 5'7" and I'm 6'6") I kept pushing the #2 button over and over with no response, cussing all the time! I discovered as you did that you have to HOLD the button. Like you said, on my Sierra, I can push the button once and it goes to the pre-set. I have the Technology package and still learning all of the features but definitely dont like the memory seat functions they way they are set up.