I'd expect the View New Posts option on the forum to display a list of messages going back some number of days. It actually appears to list messages going back to a certain date, and this date seems to get reset once a week, on Friday or Saturday. When the start date is reset, it gets set to the date when it was reset. For example, the last time it got reset was around 09:00UCT on Friday, January 11, so the View New Posts option currently list messages posted on or after January 11.
I think it would be better if the start date was reset to a date, say, five days prior to the date the reset is performed. That way the list would contain messages for at a least the last five days and at most the last twelve days.
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