An account in active directory has had its email address changed from one federated domain to another, however this isn't showing up in Office 365.
For the purpose of this solution, the following examples will be used.
An Office 365 tenancy has these federated domains:
Office 365 doesn't support the automatic rename of one federated domain to another when using AD synchronisation. It has to be done using PowerShell.
Use the Office 365 (MSOnline) Powershell modules which can be downloaded from here. The email address has to be changed to the onmicrosoft.com address first and then to the required federated one.
Once installed, the commands needed are:
connect-msolservice (enter global admin credentials)
Once this has been changed run:
And the change will now be visible in Office 365.