Fleet Code was worked on throughout the war with varying success. When an edition was in use for one month, B-Dienst would normally achieve some success in 10 to 14 days, but depended on the material available. No advanced operational material was gained from the use of Fleet code during North African Landings until November 1942. In November 1942, Germany captured an edition of Fleet Code (No. 27) in North Africa that remained in use for exercise purposes until August 1944, and B-Dienst was able read some messages, which were considered unimportant. Even during the sinking of the Scharnhorst battleship in December 1943, when B-Dienst intercepted 30 messages, B-Dienst were unable to effectively break the cipher and use it to operational effect. In January 1944, during the Anzio Assault, B-Dienst had intercepted 158 messages, but were unable to effectively use it, due to the low volume of traffic. By the end of the war, B-Dienst had made sufficient progress with the cypher, that 1500 messages were able to be deciphered monthly. It was replaced by the Combined Assault Code.
