Does adding new domain affect existing Azure AD joined devices?

[MrOrtega]

Hi, we have a principal domain on our Azure AD and some W10 devices are Azure AD joined. If we modify the domain adding a new one and making it as principal (changing the user UPN), would it affect on the Azure AD joined W10 devices creating a new profile?

[#2]

I believe the main concern here would be the ramifications of changing the user UPN and what would need to be changed in the AAD Connect configuration. Refer to this documentation on where you would need to make adjustments. https://docs.microsoft.com/en-us/azure/active-directory/hybrid/plan-connect-userprincipalname