I am rather confused with the whole access and modification.
I want the files to be cached until they are modified. If the data is the same, show cache version. If data has changed, download updated version and cache it.
I don't see why you would want anything different? All this access plus 6 months is not making sense to me. Request a new file if the last modified date is newer than the cache date. Can this not be done in such a simple manner?
I want to be able to create index.html on 1/1/2012 and have everyone cache it. I don't want it to be downloaded again until I edit it. Say I edit it at 1/5/2012 and someone who hasn't seen index.html since 1/1/2012 comes along, they should see they have 1/1/2012 cache but now the file has a last mod time of 1/5/2012 so they download 1/5/2012 version and cache it.
I never want to edit something and have a user not see it for any period of time. I want all my edits to be viewed upon next request.
How can I do this for all files?