According to TVLine, it was pulled (no reason given) to air at a late date.
Speculation is it is because of what happened this past weekend at Bondi Beach.
'NCIS: Sydney' Season 3 plans disrupted as CBS makes surprise scheduling change
'NCIS: Sydney' was supposed to air the ninth episode of its third season on Tuesday, December 16
but what's the Bondi beach incident going to do w/ episode 9? unless there is some similarity ? they pull it off just a few hr. before it should air