Possible to setup LDAP where you can login with email but sign-in cache samAccountName?

Nextcloud version (eg, 12.0.2):16.0.4
Operating system and version (eg, Ubuntu 17.04):16.04
Apache or nginx version (eg, Apache 2.4.25): 2.4.18
PHP version (eg, 7.1): 7.2

  1. have external storage configured to a SMB/CIFS
  2. i have it setup that LDAP users use email to login

When users login to nextcloud the SMB external storage does NOT mount with “Log-in Credentials, saved in session”
**When user login to nextcloud WITH samAccountName instead of email, SMB external store DOES MOUNT.

Conclusion:

  1. logins work for same account with email and samaccountname
  2. when using email to login it does not convert in the background to samaccountname -> thus SMB mount with Log-in Credential saved in session does not function -> how do i go about doing this with users only being able to use email as a login.

emails look like username@domain.com and the samaccountname is username_clientNickname in my multi-tenant environment