Comment 1 for bug 1544064

In the primary archive, these "NBS" (not-built-from-source) binaries are only removed by hand when they don't have any remaining reverse-dependencies, to avoid unnecessary breakage. This is intentional. I've restored aeskulap, though.

I think similar considerations about avoiding reverse-dependency breakage may apply to PPAs, though I'm not sure. William may remember more here.