Kyushu is entirely samura run (Tsushima depot, planet kyushu even the research base has Samurans working on it. Then you have the FA base and the Tau 42 hole leading to the Guard System of The FA) and very much conservative and pro emperor, pro farmer. So no that wont be turned into a BD monarchy ruled system.
What you say about honshu is doable. I imagine that the storage depot could turn into a fortress for Samura / emperor forces however.