I did not keep track, so more than 50 users installed the BIOS from the archive I prepared for ybbob already.
To my surprise, AN515-55 has identity data self-healing technology, which can result into consequent reboots after flashing an inappropriate firmware. The only thing that saved their devices from the worst scenario.
However, some reported that there’s an issue when Ubuntu is no longer capable of utilizing PEG device, HDMI function.