Attrition against fictional shipgirls with vast ammunition reserves

How could fictional shipgirls be defeated if pocket dimensions remove ordinary ammunition limits?

Continuous combat could exhaust them until they collapse, at the cost of hundreds or thousands of attacking ships.

The fictional premise gives shipgirls enormous ammunition stores through pocket dimensions. Their exceptional fighting power is part of the setting. Constant engagement until they collapse offers a possible means of defeat. The estimate puts the attacking losses at hundreds or thousands of ships. Those losses belong to the fictional scenario, with no application as a calculation for real naval combat.