Three units arranged as per the diagram below. As can be seen unit B has an incomplete rear rank
-----BBB
AAAB---CCC
AAA-----CCC
Units A and B are clearly in a battle line, but do units B and C also count as being in a battle line?
Or in other words, do you count an incomplete rear rank as covering the same width as the front rank, or not?
(ignore the dashes - they are only there because submitting the post removes the spaces which mucks up the diagram somewhat!)