Expires: headers for Packages.gz, Sources.gz
Would it be possible to have (at least the primary) mirrors send Expires:
headers for Packages.gz and Sources.gz? They should expire at the time of the
next mirror pulse; usually this can be estimated to be (mtime + 24 hours).
With Apache, this is as easy as adding:
to the appropriate config block(s). This would allow caches to be very
accurate about the freshness of their copies of these files.