Hi @cmkl,
As the name suggests, the ‘Existing user as verified interval’ option marks all the existing unverified users as verified.
Existing users refer to the old users who registered before our “user verification” plugin was installed. Once the plugin is activated, these old users will also be required to verify their email when logging in. If you don’t want to make it mandatory for your old users to verify their email, this function will be useful for you.
It’s important to set an interval time because imagine having thousands of unverified existing users! Verifying all of them at once wouldn’t be ideal. That’s why this feature allows you to set an “interval time.” This means that the verification process will run automatically until it finishes verifying all users, but it will only verify a limited number of users during each execution.