I'm at Jan 45, with an XXI. I play with autotargeting/TMA. So, it's a bit cheap. Even still it's damn hard now. Asdic prevents me from doing the old 'pop-up in the middle of the convoy' because convoys are surrounded by 7 escorts who detect you if you are close and you can't get teh surprise. My new solution is to pick off any escort that is travelling in a straight line with a long range electric shot, first. This cracks a hole in the side of the convoy and i enter. I kill what i can, leave, and then the next time i ambush from the same side, there's a big hole in the cover, allowing me to pop up in the middle once again.
KB
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