Jack_Poehlman , Intune_Support_Team
Have been going through documentation, blogs and other discussion boards but there is not enough clarity on this topic.
I tried Domain Joining previously enrolled devices, that didn't work. I then setup a autopilot profile and group and initiated an autopilot process on an enrolled device. Based on your comments here, I thought the Domain Join process only took place at the OOBE (autopilot) process.
But that didn't work either.
On the other hand, the MS documentation actually hints that it should be possible to use previously enrolled devices and have the domain joined
https://docs.microsoft.com/en-us/mem/autopilot/windows-autopilot-hybrid#register-your-autopilot-devices
Would be good to have either better documentation or clarification on this topic.