Offcourse that also depends on what Aurvendil and falk forces in fissoa do.
There in massive numbers, there isnt going to be a nice/decent battle if falk/aurvendil don't attack the fields.
We could have sacked the Fields in a late turn move if we wanted to, as it had what was it, a hundred men defending it? Well it's doomed to failure if we attack with just the Fissoan army defending it, let alone Fissoa and D'Hara. And we've nicely cut the Grand Duchy in half, from Libba, to Munawai to Mangai. Once Munawai and Libba revolt as well your realm will be severed in two. No sense deviating from this course.
I suppose we'll also have to consider the Lurian army turning up as well when we least expect it.
But if Aurvandil was serious about taking down Fissoa we would have sent more than one and a half armies. We're just here to put you in a position sufficiently bad to discourage any forays in Falkirk and to pressure you into accepting a peace without the conquest of Falkirk. ('Cause it always works when I try to pressure realms to peace militarily sigh).
