There was no recorded wreck at this site so it was reported to your appropriate authorities, including the Receiver of the Wreck (RoW). U-31 evaded a distribute of four torpedoes fired by HMS Trident about 15 miles (24 km) south of Lorient and was then compelled to dive when fired https://u3155210.blogkoo.com/the-2-minute-rule-for-u31-51824950