Another follow up. After less than two weeks and 13 prints my Form 3B printing speed came to a craw again. It actually happened during the last print. It started normal with typical lagging behind the initial scheduling but nothing unusual and than within about 30 minutes still remaining everything came to a sudden crash with progress almost non existent. In the end out of predicted printing time of 4 h 30 minutes it became 7 h and 22 min. Black V4 resin, 975 layers at 50/m. Part was OK but not great. I’ve noticed unusual number of layer shifts. Still usable I think. Machine was rebooted immediately right after and my next job took only 20 minutes extra to complete. It looks like from now on I need to reboot regularly at least once a week.