I have a relatively new Montana 700i. The unit and mount are new since January. I was out riding yesterday after updating to 19.20. I went around a curve, looked down and the unit had powered down. When I reviewed my track today, it looks like I caught it less than .25 miles from where it shut down. It booted back up immediately. and continued for the rest of my trip, about another hour. Battery was at or near 100%.
I thought this had been fixed, based on a few older posts.