Profile: svenA-3

Problem:

I've used a cred_save_data hook script to set up a lastname+firstname+birthdate scheme for the login name, which also works fine.

The issue: it seems that the "new user registered" confirmation mail is being sent before the script can save the altered username.

Is there a method do trigger the confirmation mail after the cred_save_data hook?

Solution:

No, there isn't existed method do trigger the confirmation mail after the cred_save_data hook.

In your case, you can ask the new users to login with their email address, it should be able to work too.

Relevant Documentation: