The Gotland retreat choice immediately changes the Swedish scenario and generates additional enemy units. Capitulation is checked at the end of the day. Occupying enough victory points before accepting the choice therefore allows the enemy to receive those reinforcements and still surrender that day. This timing explains why the retreat event is delayed until sufficient territory has been occupied.
Notable Point · 2:11:58-2:12:27
The Gotland event and surrender resolve at different times
The Gotland choice takes effect immediately, while surrender resolves at the end of the game day.