Debmirror: *remove* a distro version

[Robert Heller]

I current have a local mirror that is maintained with a daily run of
debmirror. Right now, three versions of Ubuntu are maintained: 14.04, 16.04,
and 18.04. Sometime soon, I am going to drop 14.04. Because of the way the the
Ubuntu mirror is structured (all of the package files for all three versions
are in a single tree of package files), I am not sure how to remove just the 
(older) 14.04 versions.  With CentOS, this is easy, since its repo is 
structured having a separate tree for each major version and removing version 
is just a single rm -rf command for that verison's tree.  I would rather not 
wipe the whole pool tree and re-populate it from scratch.  It is easy enough 
to edit the debmirror config file to remove the old version (trusty), but how 
do I clean off the older package files cleanly?

-- 
Robert Heller             -- 978-544-6933
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