Does anyone else fear updating manager as much as I do?

Just checked the release notes for this, I don’t see anything about this tax change or the tax changes in:

You’ve made a fundamental change that has caused me (and I suspect others) some grief.

Users have had to develop ways to account for things that manager couldn’t do, or poorly implemented, in the past. When that breaks, you really can’t blame users for doing it wrong to begin with.

I think you need to develop a tool to identify to users “stuff” (entries or outputs) that will change as a result of how manager implements features and accountancy principles. Because those sort of fundamental changes can have legal implications.