I remember being in the bar at BAe Flying College, Prestwick in Spring 1994, where some BA (ex-RAF) FltEngs were being re-trained as Pilots. One of the guys, a Geordie whose initials were MB (iirc). He was saying that he was operating on an SF squadron & all his crew got b*llockings for trying to buy postcards in local shops from "...this Chilean owned island in the South Pacific..."
Maybe true or he could well have been yet another 'Bar Stool Flyer'.
Didn't the MoD have a couple of exchange officers or personnel with the FAdC before & during The Falklands War? I would've thought that, Falklands War aside, with all the ex-RAF/RN/BAC kit that the Chileans were using at the time, HMG would've had a couple of advisers of the technical variety on site. Just a thought.
I seem to remember a black & white photo of a RAF C-130 in FAdC markings at a UK civil airport shortly after the conflict still bearing traces of its 'temporary' identity.