Change primary email when using LDAP

When using LDAP to authenticate users, the email field of a user is automatically set to the user’s UPN if a mail or email field is not available. (user principle name - which sometimes is not a real email address). Also adding a mail attribute to LDAP after a user is created does not update/add the email.

Adding an additional email using the web interface only allows the user to be identified for commits, but notifications and avatar detection does not work.

Is there a way to set an additional email to receive notifications and be used for avatar detection instead of the LDAP UPN?