Updating Bios – Soekris Info Wiki
You would need to contact the Lenovo service again, i don't think you can update the serial number and such in the bios by yourself.
Old versions continue to be available but one should not downgrade to a version earlier than that supplied with the board (for example, newer flash chips aren't supported by older versions).
It also allows you to enter antenna commands and view diagnostic data.
A P P E N D I X A – Updating the Firmware