Use UPN instead of samaccountname for Active Directory authentication
Synchronized User ID should use or allow for the use of User Principal Name (UPN) instead of sAMAccountName. sAMAccountName is a legacy attribute that hasn't been used since Windows NT. With the implementation of Office 365 our organization was forced to add a UPN suffix in order to federate our identities and most applications now support that and use UPN for login ID. STAS is not a viable alternative as the limitations are well known (logging in with cached credentials, changing network connection type, etc).