The Royal Navy needed at least twenty modern destroyer flotillas for its capital ships, carriers, and wider commitments. That figure remains a floor whether or not the counterfactual also changes capital-ship procurement. The count does not include over-age destroyers because the treaty replacement rules did not require those older hulls to be discarded. Distinguishing retained ships from modern formations prevents useful but limited escorts from being mistaken for the battle fleet's required screen.
Notable Point · 50:47-51:19
Why the Royal Navy needed at least twenty flotillas
Twenty modern flotillas are presented as a floor for global fleet duties, separate from older destroyers retained outside the treaty replacement totals.