I have a TCL U49P6046. Ever since it updated to Android 8 it lost some of the functionality I used - the Play Store apps (VLC, MXPlayer) lost access to NTFS formatted USB drives and the Instant-On function does not seem to work anymore. If I could roll back the TV to the last Android 7 build (the factory settings would probably work too) I think I would get the features back.

The issue with that is that I don't know how to prevent the TV from updating automatically - nothing in the settings seems to be able to do that. Flashing an older version might work but I don't know if that would break Netflix (which I also don't want to lose).