Does FortiNAC Downgrade support?

does fortinac support downgrade?

What is your interpretation of the following comment in the FortiNAC documentation (Typical Scenarios 3.-)?  Is it possible to revert the FortiNAC version on a hardware device? For example: Go from version v9.4.4 to version v9.1.5?

--------- FortiNAC Documentation ------------ 
Database Using CLI
Typical Scenarios:
1.- The disk fails on a RAID-less appliance.
2.- The appliance has been reset to factory defaults, and you want to restore the pre-reset 
remote backup of the database.
3.- You have upgraded the FortiNAC hardware and want to restore the most recent remote 
backup from the previous FortiNAC appliance.
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