I've had two pretty significant failures with 2019.16.2, one this past Friday, and one today. The two cases were different from one another and were also different from the failures I had on an earlier release of the code.
In the earlier release of code, when AP failed, the APE had to reset itself, which took about 10 minutes to do. During this time no cars or lane markings were visible on display. This was reproducible about 40% of the time I drove through a tunnel here in NY. Tesla fixed the issue, and I no longer experienced that particular issue in 16.2
That said, some new problems came up.
Last Friday, without getting a nag message, the car went into park and flashed the hazard lights. The APE computer was fine, and I was able to restart AP immediately. I initially thought I somehow missed the nag messages, but after speaking to support, they told me that was not the case.
Today, AP aborted 20 seconds after starting AP. This time, it just told me to take over, and I was able to re-enable it immediately afterward. There wasn't even time for a nag message to appear.
I spent an hour on the phone with Tesla this evening, and while we were on the phone, I started getting an update for 2019.16.3.2. We decided I'd try this version and see if it fails again before scheduling a service center appointment.
None of these issues have inspired a sense of comfort in AP, and I hope these issues get resolved soon.