[ I don’t mean that this is a problem and just want to satisfy my own curiosity ]
I see that right now the nixpkgs-unstable branch is behind nixos-unstable. This contradicts my received wisdom (which is that nixos-unstable is advanced when OS+DE tests pass, and nixpkgs-unstable is advanced when a more minimal set of tests pass, or maybe even just evaluation), which in turn seems to indicate that my received wisdom is wrong, outdated, or both.
What is the authoritative and up-to-date source of information about *-unstable branch/channel advancement criteria?