If you’ve been running pre-release firmware on your Mac’s T2 chip, trying to revert to a release version could brick it.
downgrade
The dust is settling: should you install Sierra, wait a bit longer, or not at all?
If you’ve been running pre-release firmware on your Mac’s T2 chip, trying to revert to a release version could brick it.
The dust is settling: should you install Sierra, wait a bit longer, or not at all?
The Eclectic Light Company 