May the broken Japanese unit in KK10 rout to the ground level of KK11, underneath the American stack at level 1 with no stairwell in KK11?
One player says no, because the router is moving closed to a KEU.
The other says yes. A10.51 reads "A routing unit may never rout toward a Known armed enemy unit ..., while in that enemy unit's LOS, in any way which decreases the range in hexes between the routing unit and the Known armed enemy unit; nor may it move toward such an enemy unit after leaving its LOS during that RtPh..." The router is not decreasing the range between the units. The range is 1 at the start of the move and afterwards there is no range because the LOS is blocked. (This treats the term "range" in A10.51 like a line of fire and not distance.) Also, the routing unit is not moving toward the enemy after leaving it LOS because it doesn't leave its LOS until it enters KK11.
One player says no, because the router is moving closed to a KEU.
The other says yes. A10.51 reads "A routing unit may never rout toward a Known armed enemy unit ..., while in that enemy unit's LOS, in any way which decreases the range in hexes between the routing unit and the Known armed enemy unit; nor may it move toward such an enemy unit after leaving its LOS during that RtPh..." The router is not decreasing the range between the units. The range is 1 at the start of the move and afterwards there is no range because the LOS is blocked. (This treats the term "range" in A10.51 like a line of fire and not distance.) Also, the routing unit is not moving toward the enemy after leaving it LOS because it doesn't leave its LOS until it enters KK11.