To retrieve the list of meetings to send the reminder of, we use a time period. However, the time interval changes according on the frequency set for the cron job. We should make as configuration item the cron frequency to be sure we retrieve the correct meetings.
Fixed in http://git.fedorahosted.org/cgit/fedocal.git/commit/?id=f770bb89a693f6108c31298ab3057ec13f12761a