On the closed pre-review thread, I attempted to remove a reviewer. Editorialbot said it succeeded, but that reviewer was still on the newly opened review thread.
prereview
review
I subsequently removed them again on the review thread. However, there is a bug here: EditorialBot shouldn't have told me success in the prereview thread, or it should have edited the review thread too.
This may not come up much. I am just testing the system because I'm not familiar with it yet.