To to translate:
771 Sqn - Search and Rescue
814 Sqn - Anti Submarine Warfare (ASW) Merlin - Based on big ships, go find and kill submarines or search for surface ships.
815 Sqn - Lynx and Wildcat helicopters onboard frigates and destroyers for ASW torpedo delivery, surface searching for stuff and other general aviation things. Insert boarding teams by fast rope and have the Maritime Sniper Teams embarked.
820 Sqn - ASW Merlin as above based on frigates doing similar thing to the Lynx but also finding submarines using passive and active sonar
824 Sqn - ASW Merlina same as 814 Sqn
845 - Seaking Mark 4 and being replaced by Merlin troop carrying helos. Work for Commando Helicopter Forces. Taxi service for green jobs etc
846 - As above for 845 Sqn
847 - Commando Helicopter Forces Lynx for recon and other such things.
849 A&B Flights - now 2 sqns (857 and 858?) Seaking Mark 7. Provide ariborne survilliance. Very capable at detecting and tracking air and surface contacts.
Alfred - 854 and 857 are the two new SK ASaCs squadrons. I'm guessing that 849 is now the HQ unit for the type (in the same way as 899 was for the jet we dare not mention lest Yokel links to a thread on PPrune...).