@Mike Gaum, Thanks for posting in Q&A. For the users converting I am not familiar, but from Intune side, if it is enrolled before I think the device is Microsoft Entra Hybrid joined. To change to Microsoft Entra join, I think we need to unenroll the device and enroll again with other enrollment method like Windows Autopilot Microsoft Entra join, Automatic enrollment+ Microsoft Entra join method
https://video2.skills-academy.com/en-us/mem/intune/fundamentals/deployment-guide-enrollment-windows
Hope the above information can give you some help.
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