On 9th July 2013, WhiteFriar and I attempted this but didn't quite make it, endiing up with all five rings, including their bonus caches, but running out of time to do the three medal caches. Never-the-less, this represents 62 'Unknown' caches in a day, comprising 57 puzzles and 5 bonus caches, and is by far the most, of this type, that either of us have done in a day.
As a consequence we are comfortably qualified for Forty Sortie (Challenge Cache), more than comforably qualified for The Puzzlers Challenge and have made substantial progress with Mystery Cache Challenge.