To err is human

I’ve rewritten The British War Office Cypher using information from TICOM report I-51 and the War Diary of Inspectorate 7/VI. I had written that the Germans were able to read this system from early 1941 till summer ’42 which was not correct. It seems that they first solved messages in summer 1941 and this was back traffic from late 1940 and early 1941. Then in the period September ’41 to January 1942 they read current traffic from the Middle East, especially during the Crusader offensive.

I have also corrected this in other essays mentioning the WOC.