Very helpful, thank you! I was under the impression that collusion wasn't allowed, perhaps at a national or international level event the kind of work those three were doing wouldn't have been allowed. But at a weekly series for beginners, I can understand it being allowed.
While I won't dispute that the third rider has every right to move out of the lane like that to get some points, I'm fairly certain that he was just doing it simply to block me from attacking, getting points or just to simply scare me away.