That's a use case for the good 'ole iterated number! Eventually you roll off the end of the history check, and can reuse the original on the next iteration. I

That's a use case for the good 'ole iterated number! Eventually you roll off the end of the history check, and can reuse the original on the next iteration. In my practical experience, I've never had a site where this happens with an account lock on bad password aggressive enough to lock me out before I find the iteration I'm on.