Apologies for the late response. (Also, you know, linking would've helped instead of just copy/pasting the thread titles.)
I was wrong in my last reply. It must've slipped my mind that we had deactivated the bumping feature a while back. For the time being, my guess is stale caching on the CDN side, which should clear itself eventually. (If it doesn't, your best bet is to unsubscribe from those threads or delete them from your subscription then re-subscribe again.) Upon further inspection, however, there might be something wrong with the threads themselves. We'll have to review them for now.
Sorry for the inconvenience.