If a BG in corner to corner contact only pursues a routing enemy, along with the BG in, previously, front edge contact and all pursuers and routers move the same distance, the corner to corner group remains only in corner to corner contact. Does the routing BG loose a base for the enemy in only corner to corner contact with it as well as the BG that will be in full contact?
If a BG is only in an overlap position that unit doesn't pursue. But if two or more BGs pursue and catch the broken BG then you lose one model for each BG that made contact after the rout.
The overlapping BG counted as in contact for the melee that caused the rout/pursuit and had to pursue because it was in contact. So I would say that if it ended up in essentially the same position where it was able to cause hits in melee but now it is in contact with that BG as routers, it must cause an enemy router's base to be removed?