Fresh Eclipse update site for every release

we have recently been reminded that cleaning up old releases from our website would be a good thing.

https://issues.apache.org/jira/browse/UIMA-6427

I have done that for the source/binary releases, but the question how to handle the Eclipse udpate sites is still somewhat open.
It seems that currently, our Eclipse update sites contain multiple releases. I.e. whenever we do a new release of the UIMA
Java SDK or UIMA Ruta or such, the existing update site is checked out from SVN, the new release is added to it, and then
the updated site is committed back.

When I speak of "update site" in this mail, I actually mean the "sub-sites" we maintain for uimaj, ruta, uima-as, etc. and
not the generic top-level "composite update site" that is usually not touched at all during releases.

We have a process described on the website to regularly "archive" update sites and start them freshly:

https://uima.apache.org/dev-eclipse-plugin-archiving

But this is something raising the question of: when should we "archive" the update site?

I believe things would be cleaner if we didn't update the update sites at all but instead always archived the
previous update site and created a fresh update site with every release.