To my knowledge the level of granularity you're after isn't possible. I.e.
you can't do a "backup stgpool <somepool> <copypool> filetype=active" where
it makes a copy of only the active files (most recent files that are still
on the server).

To facilitate what you're after you'd have to do something to ensure the
initial pool you're going to be copying from has only the files you want in
it. This probably isn't practical though..e.g. set retention so you're only
saving the most recently backed up copy. Or do a 2nd backup into another
pool such that it only has the most recent files, then copy from that pool.

So unless someone has a better idea, I don't think it's possible.

Gerald Wichmann
Sr. Systems Development Engineer
Zantaz, Inc.
925.598.3099 w
408.836.9062 c