Apple ceased supporting macOS Sierra with the release of Catalina in early October, and subsequent security updates which have brought firmware updates have only been made available for High Sierra and Mojave. This leaves Macs which are still running macOS 10.12 using older and unsupported firmware, which will almost certainly never be updated.
I have therefore moderated the messages given in SilentKnight when run on Macs still using Sierra: instead of marking an old firmware version as being out of date, SilentKnight version 1.6 now warns the user instead.
SilentKnight version 1.6 is available from here: silentknight16
from Downloads above, from its Product Page, and through its auto-update feature.
Because the command tool version
silnite isn’t used in the same way, I haven’t altered its behaviour.