Foreknowledge of U-boat numbers accelerates British escorts

What would Britain do if it knew early that Germany would build hundreds of Type VII, Type IX, and Type II U-boats?

It would probably begin building more sloops and Flower-class corvettes earlier, though that knowledge would amount to foreseeing Germany's later wartime production.

The scenario grants Britain knowledge Germany itself did not yet possess, since the cited totals were wartime outcomes rather than a fixed early plan. With that warning, the likely response is to accelerate escorts already suited to anti-submarine work. Earlier Flower-class corvettes and sloops would expand convoy protection before the U-boat campaign reached full strength.