The recovery firmware in v0.8.6 fixes this issue.
(You can also download the recovery.itb file from here and manually update )
It will refuse to set environment variables if the U-Boot environment appears to blank/missing or corrupted:
$ mtd erase ubootenv
$ baremetal-deploy traverse-openwrt-arm64 /dev/nvme0n1
...
ERROR: The U-Boot environment on flash is missing or corrupted
Not setting the management mode variables (gbemode,sfpmode) because of this
Reboot your system and use these u-boot commands to get back to a normal state:
env default -a && saveenv
Separately ./flash.sh now prompts to reset and save the environment on next boot, so the situation with an unsaved environment is less likely to occur.