And this is total ********, there is no version or variant name number checks (although variants are usually generated in descending order so those timestamps make it seem that there is variant name check). The only check that there is is swcert timestamp. (as you can also see in error message that the number in that row is certificate creation time in seconds since 1.1.1970.) If your flashimages swcert timestamp is older than the swcert's timestamp on device, you get "downgrade disallowed. ([timestamp])"-error message.