Read-through/write-in notes today flew, with Book 2 being a remarkably clean first draft (not even a lot of typos)…
…Right up to the point where it wasn’t.
In the last three novels, I changed some of the worldbuilding that I did in Two to something much better. And when I ran into the spot where I’d used OLD worldbuilding on page 221, I ended up doing a hard re-think on how I could save most of what I’d written in the next few chapters while still removing one BIG change that could have cost me about three to four chapters.
Got it, managed to do it while only killing about 250 words, and tomorrow I’ll get to write a nifty bit of new stuff that makes the world a little weirder… but while NOT BREAKING later worldbuilding essential to the rest of the five novels. (And, if the first five find their readership, more books beyond them.)