So the date Nov. 29 seems to be the favourite sofar.
Yes, the escort for the next convoy back to Loch Ewe, RA 62, was the same as the escort for the inward JW 62. RA 62 is the one in which Tunsberg Castle was sunk, according to Bob Ruegg/Arnold Hague (this is where my confusion comes in). The escort for RA 62 actually did leave earlier than the rest of the convoy in order to attack the U-boats that had assembled (U-387 was sunk during this period). The Luftwaffe attacked on Dec. 12 with 9 torpedo bombers, 2 aircraft were lost but no ships.
(My page Arctic Convoys [www.warsailors.com
] has more on this).