There is the possibility of SpecOps in the Porpoise, as well as with the Salmon, Sargo, etc., beginning about mid-1943. The Narwhal Class is almost exclusively SpecOps, but is not available there until 1941. It's missions out of Pearl have some SpecOps beginning in 1943 also, and it then transfers to Fremantle for 1944... You can use a text editor to open the "Game /Data /UPCData /UPCCampaignData /Flotillas.upc" file and see what boats are where when, and what they do. It is a bit daunting to look at initially, but in conjunction with the PatrolObjectives.cfg file, is what controls what the boats do in the game...