If I remember the AU30 were targeting German Naval HQ at Dieppe.
Even if they did manage to pinch one of these machines the Germans would have noticed it and changed the codes.
I don't know if you saw the documentary which aired on Canadian History Channel last summer
The documentary was such a snow job, portraying Flemming as the master planner of British intelligence operations when he was just of one of many midstream officers.
Last summer the History Channel aired a silly documentary on the Dieppe raid which claimed the raid was an elaborate cover for Flemming and his commando group to pinch a U-boat code machine.
The reality is that Flemming and his group had nothing to do with the planning of the raid. They learned about afterwards and asked if they could tag along, drawing up their own targets, etc.
Also Dieppe was not used for U-boats so where they did get this idea they find an enigma machine?