Prominer,
on AIS there appears to be some issue loading as you say and plenty of boats waiting.
Yesterday CSL Whyalla was doing the rounds Ok. May be one barge out of action or tugs just not available to tow barges for a while,or some industrial action???
http://www.marinetraffic.com/en/ais/home/centerx:137.6/centery:-33.2/zoom:12
Suspect they have done around 1mt for Jan or thereabout.
Fitnfam