Belch
Midfield
I found it strange that at the beginning they touched on the subject of the number of U Boats being lost, but obviously unaware that the Enigma code had been cracked, I think they could of developed this into a better storyline.
The Allies weren't cracking the German Naval Enigma codes at the time that the new series is set (Autumn '42) because the Germans had added a 4th rotor to their Enigma machines.