Ignoring old articles

[dreemt]

In my Settings I have "Avoid adding articles before this date/time into the database" set to this month.

I added a feed and fetched the articles. Then I changed the date to last month and re-fetched. I can see the older articles from last month.

I added another feed and fetched the articles. Then I changed the date to an earlier time and re-fetched. This time older articles do not show up.

If I delete the feed and add it again, the fetch uses the updated date in Settings.

Is fetching after changing the date in settings supposed to affect what gets downloaded? Or is it supposed to be fixed at the time of the first fetch?