There was no recorded wreck at this area so it was described on the pertinent authorities, including the Receiver from the Wreck (RoW). They ended up regarded as superb boats. During the war 8 were sunk, 3 surrendered and ended up at some point scrapped, and two were deemed lacking. https://u3123211.ampedpages.com/the-best-side-of-u31-61095984