I have a bunch of Watch Topics set to update every 90 minutes. I look at them, download what I want, and then delete everything.
Every time the Watch Topics update, they pull in everything that matches my search terms, for the past 7 days. This seems to be new behavior that started about a week ago. In the past, it would only pull in things that were new since the last search.
Is this a glitch in Newsbin, or a search problem on your end?