'I think I know what actually happened since something related just recently happened to me.
As I was driving on the highway on a road with markings from construction on AP, I was looking down at my phone for some time. My attention was not on the road, but, the car was on autopilot. I thought the markings on the road was correct, so I didn't look at the road. Well, because I was distracted on the phone, the car nearly hit the side barrier from construction. I just took a brief look to my side and just happened to took control. If I had not, I would suffered a bad accident.
I now am suspiciously that the driver of MX Accident had been distracted. AP didn't know the road markings are worn and made it think it was a valid road.
Glad you weren't in an accident! Hopefully you have a much healthier respect for APs limitations now. I know that after I got hit by a distracted driver my husband and I vowed to never glance at our phones even with AP on. In the past I have done it before, but having someone looking at his cell phone almost hit me head on was a huge wake up call.
It only took the guy 2 seconds to hit me - I would say I am guilty of having glanced at my phone for 2 seconds in the past.