Hey HnH/Jorb!
Was hoping to see more interaction with Lye and ways to make it based on some other realistic and immersive methods. Specifically giving limestone and most importantly fossils another use. Grind limestone/fossils at a quern, get slaked lime and boil it with ash to get lye in larger quantities. Boiling ash does work but... it's the least efficient method comparatively as it uses the natural minerals in water to take the same relation that limestone or the calcium carbonate in the fossils could provide.
https://cavemanchemistry.com/oldcave/projects/lime/index.html for reference.