I noticed that my Category pages were out of date last week. April 18. I then manually deleted my whole cache. This fixed the problem.
I then checked today, and saw that my Category pages were again out of date. WP Super Cache is serving the pages generated on April 18. We've had several new posts in this category, so I would assume they should have been updated.
I believe when I first setup WP, this was all working properly. I would also assume, this would be a default behavior for WP, clear the category cache file, when a new post is added to that category.
Am I missing something?
I do not want to check "Clear all cache files when a post or page is published or updated.", as I think this will clear all files, including single entries, which I don't want.