 Twelve minutes later, "Porpoise" submerged with both vessels making their way back west towards a forward operational base at Pedjantan Island.Over the next two nights, 29–30 September 1944, the Rimau commandoes, the SBs, folboats and other stores were transferred from "Porpoise" to "Mustika".Once completed on 1 October 1944 the second conducting officer, Major Walter Chapman and "Mustika"s Malayan crew returned to Australia in HMS "Porpoise".