October 29, 1927. Choson Peninsula.
The Ruthenian Armed Forces have captured key cities in the northern part of the Choson Empire, continuing their assault from one city to another until the capital is in their hands.
The Yamato Forces stationed in the Choson Empire were desperate to turn the situation around and sent all of the troops garrisoned in the south to the north to stop the Ruthenian Advance.
There hasn't been a reinforcement since the invasion of the Ruthenian Empire started. The aircraft providing air cover was supposed to protect them from the deadly rains of Ruthenian firepower. But they kept getting intercepted. Even though the Ruthenians never targeted their airfields that would render them useless for strategic purposes.