Hi there. As a person who also worked with day/night as a motif I was very excited about this module. And you really have some interesting ideas. I wish there was a category for originality, because the time loop and jumping between the Dayscape and the Nightscape is a neat mechanic. I was thinking about a similar mechanic for another idea I had, inspired by a game dev friend of mine's mobile game The Silent Age. You should check out that game, it's really nice. There are also, by now, quite a few time-loop games, so I would check out those for how they manage the inner workings of that.
Now regarding your module, I found it quite hard to wrap my head around it. Like take the introduction for example. It seems like it perhaps comes out of a discussion in discord about Regent is the Prince etc (correct me if I am wrong), but for someone who didn't follow that, it felt a bit technical and verbose. It at least could get to the meat of the module faster.
Then take the warden notes of "The dayscape is caught in a loop, the nightscape exists after the loop, as well as during the loop". This seems needlessly confusing. Is it after, or during, or maybe the nightscape just exists? I am not sure what is meant, so I cannot give a suggestion how to improve this.
Then there are a lot of descriptions of mechanics that don't feel like they integrate with mothership. Like in Rifts "there's a 30% chance of disappearing with a pop...". When and how? and shouldn't it just be a d100 roll?
Layout-wise I would also work with the usability of the map. It seems like flipping would be happening a bit during a play session. It would be nice if the areas that are the same would align when flipped so there is less cognition used on finding the corresponding area.
Again, Theme, ideas and art are great. I would personally look at improving the writing, layout and utility of the module, and a bit of Mothership game design streamlining.