If the British had already been reduced to their 19 flagged VP, either because of conquest, or previously strategic warfare results, well then it would make a difference whether or not I had to hit the 10 intrinsic PP before I hit the LL, or if I could hit LL first.
The way we played it effectively some amount of my SW shots were lost, but nonethe less LL git through.
We subsequently reread the rule and doubted if we had played it right.
I had a ton of submarines. Just about every British convoy was being fired at, by the time I got to the last North Atlantic convoy I had already eliminated PP so that all that was left was the Flagged PP, which I can't hit, and then the LL.