The player statistics were updated yesterday to include puzzles played in September. In Chinwag, long time player jeff queried the accuracy of the data. In particular he suggested that there was a Challenge puzzle left out.
It looks like he was right. From what I can see none of the details from the Challenge puzzle of 22 September are currently reflected on the player stats page. This is no doubt another consequence of the long drawn out process of migrating to a new server late last month.
I think the error can be fixed. Watch this space for further announcements.