Metropolitan Comms Sqdn was at Northolt after Hendon closed. Fighter CCS and Coastal CCS were both at Bovingdon, joined by Bomber CCS when Booker closed as an RAF station in about '63, then the three amalgamated to form Southern Comms Squadron.
Last Neptunes I saw were operating off the Shetlands in Sep '72, when I was briefly stationed at Sumburgh as part of my ATCO Cadet training. They seemed to operate a patrol which took them southbound off the east coast of the islands, and never called Sumburgh approach, whilst Nimrods always did. I presume the Neptunes were Norwegian or Dutch.