Admin report for changed email addresses?

Support
1

I have the need to watch users changing their email address.
(Background only: We have another system to maintain members for a sports club with their email address - only users with an email address from this external system are allowed to be in the forum. Changes should be kept in sync - but not enforced hardly)

Where can I see user initiated changes of email address? It is ok for me to use pg SQL, probably preferred because it could be automated then.

Thank you
Thomas

2

Set the other system up as an SSO provider, and only allow logins through that SSO?

3

Good idea, but the other system is a traditional offline member management system.

So I am looking not for a stronger coupling, but for either a notification or an on demand query to find address changes.

(The max amount of users is under 1000, changes will happen rarely. For now this is done manually, but after a while it might be partially automated)