This is the current message for unversioned-copyright-format-uri:
N:
N: Format URI of the machine-readable copyright file is not versioned.
N:
N: Please use
N: http://anonscm.debian.org/viewvc/dep/web/deps/dep5.mdwn?revision=<revisi
N: on> as the format URI instead.
N:
N: Refer to http://dep.debian.net/deps/dep5/ for details.
N:
N: Severity: pedantic, Certainty: possible
N:
N: Check: source-copyright, Type: source
N:
However dep5.mdwn no longer exists. It apparently got replaced with a
directory. So the information given here is wrong.