I’m always puzzled with the mapping of the internal version numbers to the device OS versions.
@rickkas7 usually has a lookup table for that, but I can never remember where
I just know that v324 should be 0.8.0-rc.25 and v325 is rc.26
The second part of your question: There is no purpose in having the factory location empty, but since there currently is no rock-solid version it’s little use to populate it with a known to be buggy version.
Once a stable version is locked down, I’d assume it’ll be placed there.
I know for the Spark Core there is a CLI command to flash a custom firmware image to the factory location.