Several units move back to secure the area most open to attack, while the remaining army stays one move from the campaign map's overseas transfer point. That position keeps a useful reserve available for rapid deployment. The force can answer trouble in another theatre without scattering units across every province in advance. The campaign treats readiness as a matter of location as well as troop numbers.
Notable Point · 4:29-5:16
Keeping a rapid-reaction force close to overseas routes
A reserve positioned near the campaign map's transfer point can reinforce another theatre quickly while still protecting a vulnerable local approach.