The Deterding operation (DT) is described on pp. 196-7 here. Poynter's record is on the 2nd link; apparently he took part in the "Great Escape".
BERWICK should have been in the Med. at the time.
Nick
https://sjohistoriskasamfundet.files...8/fn68_a05.pdf
https://www.unithistories.com/office...fficersP2.html