I discovered skybox image changes very odd way every evening right at 21:30 of in-game time.
It affects both skybox darkness gradient and stars background. Basically, darkness gradient (that covers about 1/3 of sky at that moment) suddenly disappears. Stars background image, at the same moment, is replaced with another similar image… or it’s skybox simply rotated.
The glitch takes only a moment, right at 21:30, to change the skybox, so if a player is doing something else at the this moment, it’s likely he will not notice anything happened to the the sky.
How to reproduce
Simply look closely at the sky between 21:25 and 21:35 (of in-game time). It will take you a minute or two. Rattay mill is a good spot to do it, but skybox changes the described way regardless of the place.
Look how dramatically different sky looks on the following screenshots. Screenshots for the same camera angle were made at 21:29 and 21:31 of in-game time (it’s less then a minute or real time).
1 - Angle one: screenshot at 21:29
2 - Angle one: screenshot at 21:31 (darkness gradient completely diapered, stars disposition vastly changes)
3 - Angle two: screenshot at 21:29
4 - Angle two: screenshot at 21:31 (same: darkness gradient completely diapered, stars disposition vastly changes)
Please, fix it!
1.9.2, PC, GOG-version