Issues with updating loginID and Intune updating loginID on iPhone

Whenever I change a loginID in AD (JDOE -> JSMITH) and change their last name in AD, in SETTINGS/PASSWORDS & ACCOUNTS/COMPANY EMAIL/ACCOUNT their registered iPhone updates the email address, to jsmith@company.com, but her username still shows jdoe@company.com  It will remain like this until the weekend where the username mysteriously changes and shows jsmith@company.com Monday morning.

We tried unenrolling / reenrolling the device and forcing a full sync with Azure AD but that does not work until over the weekend.  Any suggestions on how to force the phone to update at the time we change her loginID in AD?