My understanding is, that in Poland the sun actually rises at 3 am. I'm in the U.S., and that sounds crazy to me, but considering that the Northern Kingdoms isn't in North America, or even on planet Earth for that matter, it's never been something that bothered me.
I would ask, if you're on PS4, do you ever suspend the game? I noticed that when I switched apps to watch Hulu plus, and suspended Witcher 3, that all the hours I spent watching on Hulu counted in the Hours played. So, if you're worried about the hours played getting padded...don't suspend Witcher 3. You have to close the game. If you go straight to rest mode while in the game, it'll suspend it too. So, if you put the PS4 into rest mode while running the game, those hours you're sleeping will count as well.