Password expiration notification not working

Hello.

We have set up all user passwords to expire within 10 days. We have set up password expiration notification emails for all users on 10, 5 and 1 days prior to expiration. The we had a test group of users reset their passwords at a given time.

So users receive the emails and most do not. At least one user received all 3 emails at once when they were disconnected from AD.

Okta does not seem to have the logic documented and available for how this automation works. E.g., An 10 day notification automation running on July 10 at 11pm will notify all users with passwords expiring within 12 hours of July 20 at 11pm?.

I would like to understand the logic and see if anyone else has had this problem.