Hi I don't have much on German surface units, U-boats being my main hobby, however the book [Hitler's Forgotten Flotillas ISBN 978-1-4738-8939-3] by Lawrence Patterson give a good account on the small surface units within the Kreigsmarine. Mentioned of the R-boats that operated in the Channel area at the time in question are from April 1940 under the control of FdM West, commander Kzs Friedrich Ruge. The 2nd R-Flotilla, with 8 R-boats. Established 1938 and was operational 1939-1940 in North Sea then 1940-1944 off the Netherlands. The 3rd R-Flotilla with 7 R-boats, established 1939 and was operational 1939 in Bay of Danzig, 1939-1940 North Sea and then 1940-1941 off the Netherlands and Northern France. As for individual R-boats histories I have no day to day operational placement details, as they were apparently moved about as the areas of operation grew at this time. Regards John