The growing body of knowledge was rapidly put to use by the Admiralty.
As June 1941 opened, and the naval traffic was read currently, it was able to make an almost clean sweep of the supply ships sent into the Atlantic in advance of the Bismarck, disposing of seven out of the eight.
This bulldog action, however, provoked a disturbing question.
In Hut 8, as they read messages about U-boat rendezvous points and so forth, they assumed quite naively that with the aid of this wonderful information, the U-boats could readily be despatched.
In June 1941 this simple view was presumably also taken by the Admiralty,
for only afterwards did anyone voice concern that the succession of sinkings, following the loss of the Bismarck, might alert the German authorities to the possibility of cipher compromise.
In fact, the operation had betrayed Alan's success, for the German authorities decided that the positions of the supply vessels had somehow been disclosed, and set up an investigation.
Their experts, however, ruled out the possibility that the Enigma cipher had been broken.
Instead, they pinned the blame upon the British secret service, which enjoyed a high reputation in German ruling circles.