As per the title:
Using the image Armbian_22.11.2_Rock-5b_bullseye_legacy_5.10.110
Formatting an nvme ssd partition as BTRFS and running the armbian-install utility, install using SPI to boot, targeting ththe btrfs partition, and selecting BTRFS in the prompt results in a failure to boot.
Reformatting that same partition as EXT4 and rerunning armbian-install (and making no changes to the data loaded to /de/mtdblock0) targeting the EXT4 partition, and the device boots using the SPI loader.