You need to configure Azure AD Connect to support the planned changes for the Montreal Users and Seattle Users OUs.
What should you do?
From the Microsoft Azure AD Connect wizard, select Customize synchronization options.
From PowerShell, run the Add-ADSyncConnectorAttnbuteinclusion cmdlet.
From PowerShell, run the start-ADSyncSyncCycle cmdlet.
From the Microsoft Azure AD Connect wizard, select Manage federation.
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