Traveling on the freeway using NoA, when I approach a slow vehicle NoA moves me over to the left lane, and then once it is safe moves me back to the right lane ("Out of the passing lane"). This is as it should be.
But sometimes after passing a slow vehicle, I see a car coming up fast behind me, and I courteously use my turn signal to have my car move back to the right lane before NoA decides to do so on its own. I'm not taking over and moving the steering wheel. I'm just turning on the turn signal and having AutoPilot prematurely move back. NoA stays blue on the screen, indicating it is still engaged.
What I find in this situation is that NoA seems to be saying, "OK, if you want to control the car, you go ahead", because if I come up behind another slow vehicle in the next couple of minutes it will not move to the left lane to pass. It just slows way down and stays behind the slow-poke.
It seems that if the interval is more than 3-5 minutes after I took over, NoA will finally resume controlling the car.
There may be other actions that will re-activate NoA, such as turning AP off then back on, but I'm not sure. It didn't always seem to work.