Hello totallyfubar,
Thank you for posting in Microsoft Community forum.
From the description above, I understand your question is related to migrate Azure AD Connect to cloud.
Since there are no engineers dedicated to Azure/ Cloud in this forum. in order to be able to get a quick and effective handling of your issue, I recommend that you repost your question in the Q&A forum, where there will be a dedicated engineer to give you a professional and effective reply.
Here is the link for Q&A forum.
Questions - Microsoft Q&A
Click the "Ask a Question" button in the upper right corner to post your question and select "Azure Active Directory" tag and "Azure Cloud Services" tag and any other Azure tag related to your products (because there are more Tags related to Azure when you type Azure key word).
If you have any question or concern, please feel free to let us know.
Best Regards,
Daisy Zhou