petro on "[Plugin: W3 Total Cache] Page cache forced to be refreshed even if exists and not expired"

Hello,

a cached page should last 4 hours in my policy, but some pages' caches are forced to be re-created before the expiration times.

For example the page: http://www.cerco-lavoro.info/offerte/?q=&l=roma
This page query string updates the result set within the page, may that change play a role in the cache generation policy?

Thanks,
MP

http://wordpress.org/plugins/w3-total-cache/