We recently had a case where a customer was using the Fresh Start process to reset a Windows PC they were using to test AutoPilot. What we were finding on the Intune side was that the device was getting a lot of the Intune policies even after a CleanPC. This is because the reset actually keeps the enrollment data and the MDM sync process will continue to work. So even though the device record was removed from Intune, when the device checks into the gateway, the MDM agent realizes it’s the same device and resets many of the attributes on the device.
For testing AutoPilot, you’ll want to use the Wipe without retain enrollment state. Here’s a screen shot of where you wipe the device: