Bletchley Park did not only attack high level machine cyphers
The intelligence produced at Bletchley Park came from a wide range of sources, not just from the German Enigma and Tunny messages, but also from other German, Italian and Japanese codes and ciphers, as well as messages in plain text or voice.
The low-level German ciphers broken in the Military Section included those detailing the actions of German police troops killing large numbers of Jews in the Soviet Union in what was the start of the Holocaust.
Naval Section in Hut 4 broke many German and Italian low-level codes and ciphers. It also carried out important ‘Traffic Analysis’, the collection and interpretation of data on the locations of the radio stations and from operator chatter, which frequently gave vital intelligence away. Reporting from Hut 4 played an important role in the sinking of the German battleship the Bismarck in May 1941.
The Air Section run by Josh Cooper carried out ‘Traffic Analysis’ and breaking low-level codes and ciphers which produced vital intelligence on Luftwaffe plans during the Battle of Britain and the Blitz, and supported allied bombing raids.