There's a great story that Tommy Flowers tells in the book about COLOSSUS, which is that when COLOSSUS was declassified and published (sometime in the 80s) almost nobody cared, because history had already been written describing what the first "real" computer was. COLOSSUS used big networks of vacuum switches to break the Lorenz SZ-40 ("Tunny") teletype crypto machine used for high-level Nazi communications. Bletchley Park was very skeptical that COLOSSUS would ever work, so Flowers (who worked at the post office research lab) self-funded the work and told Churchill he could have the machine finished in a year.
One person did care, though, and wrote to Flowers after reading about COLOSSUS's design. He was a former Nazi, German Army crypto specialist that told Flowers he had had basically the same idea for a code-breaking machine. However, when this German crypto specialist tried to sell the project to Hitler, he told Hitler it would take two years. Hitler vetoed the plan because he thought the war would be over by then.
It mentions in passing that details of the breaks were sent over Enigma which the allies were breaking, so they knew that the Germans were breaking M-209.
Timely post - Tom Perera was a keynote speaker at the Vintage Computer Festival - East the day this was posted (and Bjarne Stroustrup the next day), and spoke on Enigmas but also discussed the M-209 and SIGABA. He had an M-209 with him, and there is also one on permanent display in the WWII Communication Museum section of InfoAge, where the VCFE is held.
One person did care, though, and wrote to Flowers after reading about COLOSSUS's design. He was a former Nazi, German Army crypto specialist that told Flowers he had had basically the same idea for a code-breaking machine. However, when this German crypto specialist tried to sell the project to Hitler, he told Hitler it would take two years. Hitler vetoed the plan because he thought the war would be over by then.