Cows asked Michael J. Sullivan:

You have said in the past you write the entirety of a book series before you even publish the first book and that this lets you go back and add things in easier if you think of something great later. The question is, what is the latest you have gotten in writing a series when you had a brainstorm and had to go back and add something that ended up changing a lot in the series itself?

Michael J. Sullivan I have indeed said that (because it's true). Well, it happens throughout the entire process, so the answer is the last book of a series. In other words, whatever book I'm writing has the distinct possibility that I'll have to go back to one or more of the books before it and make changes.

Generally, they are minor tweaks - and more often than not it will be an addition (very seldom have I ever removed something). The adjustment can be as small as a few paragraphs. That said, sometimes I need to add new characters which have required a whole new scene or sometimes even a new chapter to be added to a prior book (or books). I don't think I've removed anything major, all the "big changes" come in the form of additions. Thanks for asking!

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