I also sent that question to FFE. Here is Marc's reply:
Andy, you pose some interesting questions which are raised from time to time. These conflicts arose originally in the graphic production process. Some were mistakes by the graphic artist while translating the list to the map. Others were deliberate (just as many maps have more than one town of the same name) and intended to create conflict as players arrive at a place which the map thinking it is Imperial, and find that it is Aslan, etc.
Andy, you pose some interesting questions which are raised from time to time. These conflicts arose originally in the graphic production process. Some were mistakes by the graphic artist while translating the list to the map. Others were deliberate (just as many maps have more than one town of the same name) and intended to create conflict as players arrive at a place which the map thinking it is Imperial, and find that it is Aslan, etc.