Makis' comment in post-battles file: "By the way, are you certain you can
deduct anoher factor in Lille before battle, I thought you have to decide for
the entire corps"
I did it according to the following rule. if not valid then the factor stays
with the corps.
7.5.1.1 DEFENDER RETIREMENT INTO CITY: Any forces or portion o 1f
forces upon whom an attack is declared may immediately retire into any
friendly controlled or vacant, and unbesieged city in that area but not so as
to exceed that city's garrison capacity
