We have been consistently expiring superseded binary publications removed from ppa.l.n after 30 days, and in the past we have expired superseded binary publications for warty/hoary/breezy as well.
We could contact the ubuntu distro-team and discuss a plan for expiring the other obsoleted series since breezy.
Regarding size used by BinaryPackageFile table, it's mostly used by primary archive binaries right now:
PPA: 900 / 2300 GB (live/expired)
Primary: 1900 / 166 GB (live/expired)
We have been consistently expiring superseded binary publications removed from ppa.l.n after 30 days, and in the past we have expired superseded binary publications for warty/hoary/breezy as well.
We could contact the ubuntu distro-team and discuss a plan for expiring the other obsoleted series since breezy.