Flashing AFTER you have provisioned RPMB?

I installed Windows 10 IoT to my DragonBoard, and wanted to test the TPM functionality. In setting that all up I provisioned the RPMB, which is irreversible, I believe.

When I try to re-flash to that device, it does not successfully boot. I’m shown a “Press any button to shutdown” message.

Other devices flash perfectly using the exact same image and exact same process, so I am assuming it is the RPMB.

How does one flash the device from scratch once this has been done? Is there a recovery procedure?

Thank you.