No RtFC fringes on various fringe finders throughout the whole experiment. The cause is unknown*. It was also windy with a couple of windstows.
*Update: Cause is most likely due to a rupture in the cryogenic system, which caused the receiver to warm up and loose sensitivity. The cooling system has been leaking He for the whole session since Thursday, but there was an extra sudden drop in pressure around Dec 5, 18 UT (an hour or so before the start of this experiment).