The Faction Wars phase whose expiry strips borders of meaning and opens the whole map to attack.
During the Ramp-Up Phase of Faction Wars, sector borders constrain where factions can advance. Once it expires, the borders stop having any real meaning and the enemy can attack from anywhere, which is why Carl kept Tran's 102nd Bulwark Battalion at the old trenches instead of pushing into the newly-won sector four, and turned the empty hills into The Trap Fields as an early-warning net.
The phase ends in two hours, giving way to Open Hostilities and, simultaneously, Operation Ruin.
The border-constraining phase whose expiry opens total war.