/usr/share/lintian/data/standards-version/ancient-date is in lintian 2.5.30+deb8u4.
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1 2 3 4 5 | # Any Standards Version released before this day is "ancient"
# That date has to be within 22 and 24 months in the past
# at release time
# Format is ANCIENT < Date
ANCIENT < 14 Oct 2012
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