That video does not address the second unit coming in after the previous round of combat. Can anyone answer the question: If two units are locked in combat and a third unit comes in during a later turn, who can attack whom?
Well it does if you pay attention to the lesson in general. Who you are in base contact with at the beggining of the round of combat(e.g. Init 11), then that is the only eligible target you can swing at. Very simple.
Wargamescon 40k Judge
caldera40k.blogspot.com
Hogleg - "only in my head someone bought CRP's OOP Wraithlord then stuck its toe in cover."