My comment feed (http://www.highprogrammer.com/cgi-bin… ) was emitting malformed dates, notably in the pubDate. It was missing the leading zeros on the day of the month and the hour of the day. So it would say “Sun, 9 Jun 2013 9:35:55 CDT” when it should say “Sun, 09 Jun 2013 09:35:55 CDT”. I think this is why Newsblur would occasionally list unexpected times on items, including sorting them based on the unexpected time. For example, the Newsblur thinks GUID http://www.highprogrammer.com/cgi-bin… was posted 11 June 2013, 8:00 pm, but it was actualy posted 12 Jun 2013, 9:03 am; even accounting for time zones that seems incorrect.
I’ve corrected the bug in my RSS generator, and I’m hoping to have no problems going forward. But it seems a mistake others might make and hopefully one Newsblur could easily workaround.