I've never had that problem at PC myself, so either it's a rare one or it's not actually at PC.

By any chance could you have been looking at a cached copy of that page, with old dates? Clicking Reload (or Refresh, depending on your browser) is supposed to resolve that (and sometimes does). I also remember seeing settings in my former browser -- something about how often to compare the cached version of a page with the latest one from the Internet (and it still didn't always get it right). If my current browser even has settings for that, I cant find them, and it never seems to be a problem anyway.