Multiple timelines

[Mux]

Is there a possibility to make separate timelines for multiple settlements, and world itself.

Now this would definitely break the game properly, but then again, somebody said multiplayer was impossible a few years back, and now its fully working. The only issue is time.

In other words, how badly do you have to strip the core to make this possible, and how much to you have to remake to make it work?

[Limdood]

Not really sure what you're asking...

multiple timelines could just be making a savegame file, copying it, and then playing both at different times and doing something differently.  Heck you could even run the game concurrently with 2 instances of rimworld open to the two different save files and allow Rimworld to run in background.