What can still be fixed by January 1941?

The exercise allows additional spending, although many earlier investments would have been cheaper and more effective. A fixed-budget version might have modernized Repulse instead of using Royal Oak to test whether the other R-class battleships could be rebuilt. Prewar sloop construction shows how relatively modest escort spending could have improved the opening anti-submarine campaign. Inflicting heavier early losses on Germany's trained U-boat crews would then have reduced the submarine arm's later training quality and operational effectiveness.