The regular pixel maintenance cycle that occurs when you put a Panasonic OLED into standby will run if the TV has been on continuously for 4 hours - I would expect other manufacturers to be similar. It only takes between 5-10 mins to run.This has pretty much confirmed OLED isn't for me if this the case. Wish I saw this months ago would have saved a lot of headaches!
How long would you need to leave the TV in standby for, until it was "safe" to use again?
I occasionally have my OLED on for more than 4 hours I suspect, but never think to turn it off purposely after 4 hours just to run the cycle. Don't get me wrong - I take a lot of care with my OLED, but even I would consider that a bit unnecessary. IMO, the important thing is that it does run once you've finished your session.
However - saying that - I probably would consider doing that if the TV was going to be on all day, every day though. In that case, putting it into standby for 10 minutes while you make a drink/snack/meal once or twice a day isn't exactly a big deal. The TV's LED will normally tell you when the cycle is running.
If you tend to leave it on all day on certain problematic channels, then uneven pixel wear ('screen burn') might be an issue in the long term, depending on your chosen picture settings and exactly what the TV is left showing. In that case, an LCD may by the better, worry-free, option.