I have experienced the black screen, as described here. Seems to happen on some channels only. Regular broadcast channels seem unaffected.
After the latest TVOS update. My screen ATV settings reverted back. I seem to be getting a solid two hrs use before black screen.
I then just close the app and reopen the app. When I watch PIK I start by closing and opening the app too.
All in all a manageable annoyance for me. PIK is still a great deal and nicer on a ATV.