Missing updates from feed with non-chronologically ordered items

Newsblur hasn’t picked up recent items from this feed:
I guess it is because the last item in the feed is older than the updates?

At the time of writing it is November 19th and the feed contains, among other dates, updates from November 18th but the last item is dated November 6th. Newsblur does not show any entries since November 6th.


And the same happened with a feed where the “most recent” items are dated to “9999 SomeMonth SomeDay”. Those items stay at the front of the RSS and they make Newsblur to hide all the following content “as read”. I understand that these are broken feeds, but it could be fixed on the reader side instead of emailing all the broken feeds providers if even we notice that something is wrong (unfortunately RSS is not high priority these days for webpages). I noticed this one only by accident and by that time I “lost” about 10 items a day. An example is: http://blog.hu/rss/feedtag/konzum+bloghu

Unfortunately(?) the PNAS feed has been updated so the example I wrote doesn’t apply. Newsblur still doesn’t show the latest items though: it has items from November 11th now, but not the 18th and 19th.