Hi @Andreas
Thank you for asking this question on the **Microsoft Q&A Platform. **
The Azure AD Connect uses the domain controller to get the user information and connect to Azure AD via HTTPS with user authentication, so you shouldn't have ani issue.
I recommend you first change the IP of the domain controller that has the Azure AD in Staging mode, after that, convert it to the principal Azure AD Connect, and then change the IP of the other Domain Controller.
Hope this helps,
Carlos Solís Salazar
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