Thank you, Michael. That's good news that UC 56's KTB is at Freiburg after all. Also, useful anyway that UC 56's orders rule it out from a Boyardville escape.

I understand your point about the patrol area of U 93. So, it may well come down to either U 84 or UC 50.

I also understand the fractured nature of the various u-boat commands and the difficulty of co-ordinating missions. However, I reasoned that Suadicani would in no way be operating without direction and, presumably, Karl Bartenbach would have the rank and reach to make contact with another command. There was an overall national imperative to get experienced u-boat commanders back to sea as quickly as possible in order to meet the monthly sinking targets / promises; and there was the attraction of further rescues, if this first was successful. I also thought that a larger boat that was going to the area anyway would be convenient. It might be better provisioned to keep station for five consecutive nights (perhaps active during the day), would have more room for two extra men, and might (?) carry a larger collapsible boat (the 'Berthon') to get some distance from the u-boat to the shore, which Suadicani estimated to be '5 miles de le côte' (the responsibility of calling off the attempt was left with Gerth if the seas were too rough close to shore). I think it might be too quick to write this off this possibility as unlikely.

Of course, it is always possible there was only one intended boat. The document is, after all, only a decoded translation from the German into French. However, it seems to be to be explicit and lucid. There is discussion about the 'rescue' u-boat and then, separately, the Suadicani letter states:
'De plus, Rudi' (French insert: 'probablement un Commandant de sous-marin de la Flottille des Flandres') - 'est actuellement en route vers cet endroit pour se renseigner pour la répétition en Février*, d'autres nouvelles suivront.'
* During the next full moon.

Best wishes
Chris