FWIW I don't actually think that was ever the case with the war with BT (losing people at general with no enemy PCs there). We did make the mistake a few times of not killing the barracks keeper, which meant BT masters would just flee and reissue master mobs once one died, to bring in and rescue the patrol soldiers.
I think the idea of an ultimatum week for RP is good, followed by a week of the chance to fight if things don't work out.