LadyAtco
I could be wrong ( he normally is I hear the cry! ) but IIRC CAA lost the Hurn contract to IAL in 1979. IAL had a 7yr contract and lost it to Airwork in '86.
I can associate certain names with the changes ie Graham Lake, who I knew at LATCC, moved from JJ to work for IAL at HH. My old nav' mate Jeff Berryman (RIP ) started at HH with Airwork in '86 etc etc.