As also noted at the very top of the main description:
This mod is deprecated and does things in a suboptimal way, on all surfaces, which might interfere with other mods.
Please use Clockwork or other mods which don't have these issues and offer more features (like changing dawn/dusk times).
It's perfectly safe to remove this mod from the game and install any other one at any time.
Is there any problem with using that one instead, or did you miss that bit and those big "DEPRECATED" signs next to mod name and description?