Assign user type for SAML users

I currently manage a CMS installation with SAML integration into Azure AD. In our organization, the only users that have access to the CMS also need Super Admin permissions. Currently what we do is have them login, then manually make the newly created Xibo account a Super Admin. Is there a way to avoid this manual step? I tried playing with some settings (specifically the usertypeid field) in settings-custom.php, but nothing seems to be automatically assigning the Super Admin user type to the neewly created users. Note that I also have the default user type set to Super Admin in the CMS settings section of the web UI. Is there something else I’m missing, or is this just simply not possible?