Thanks to CHUCK MYLES (1068-1989) for this huge task of compiling all this data. Every time a U-Boat took on fuel in any foreign port, on the high seas from another U-Boat or a surface ship - any way at all the a U-Boat took on fuel, CHUCK put it on this list. Here we learn:

U-600 took on fuel from either U-462 or U-463 about 7 August, 1942. Both U-tankers were on the same station, and there were two refueling operations on this patrol of U-600. U-600 departed her home port (the 7th U-BootFlotille at St. Nazaire) on 14 July, 1942 and proceeded to the Caribbean where she undertook the first refueling operation. They engaged Convoy TAW.12 and her patrol continued until about 27 August, 1942 when she took on fuel from the other U-tanker for her homeward journey. She arrived her homeport on 22 September, 1942.

U-598 departed her homeport (the 6th U-BootFlotille at St. Nazaire) on 7 July, 1942 and took on fuel from U-463 about 7 August, 1942. During her patrol, U-598 engaged Convoy TAW.13 in the Caribbean, then took on fuel from U-463 again for her homeward journey. She arrived her homeport 13 September, 1942.

U-658 departed her homeport about 7 July 1942 for the Caribbean where she took on fuel from U-463. She engaged Convoy WAT.13 and then Convoy PG.6. About 27 August, 1942 U-658 took on fuel from U-463 again for her return voyage, and she arrived her homeport 12 September, 1942.

U-564 departed her homeport (the 1st U-Bootflotille at Brest) on 9 July, 1942, took on fuel from U-463 about 7 August in Grid Square CD before going on to her patrol area to the northwest of the Caribbean island of Trinidad. She engaged Convoy TAW.S to the west of Grenada, then patrolled through the Caribbean and departed her station about 31 August. she arrived her homeport on 10 September, 1942.

NOTE - the log of U-463 shows that she gave fuel to U-564 twice during this patrol, but we can locate only one reference to the refueling of U-564.