Hi @Gurudas • Thank you for reaching out.
Yes, when a user account is synced from On-Premise AD to Azure AD, the changes made to the account in On-Premise AD are automatically synced to Azure AD at the next sync cycle after the changes are made.
The sync cycle runs every 30 minutes by default and can be customized as per your requirement. You can check the current sync cycle interval by running the Get-AdSyncScheduler
cmdlet on the AD Connect server:
To manually trigger the sync cycle, you can use the below cmdlet so that you don't have to wait for the configured interval to sync the changes.
Start-ADSyncSyncCycle -PolicyType Delta
In your case, if you change the display name from John.Dave to John_Dave in the On-Premise AD, it will automatically get updated in Azure AD after sync cycle runs automatically or with a manual trigger.
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