Yes, there were reserved frequencies, 145.550 was for medical. When I was there, there were only 2 repeaters, and really these were to teach children with, and not for general use, but outside 9–4 Monday to Friday others could use them.
The old telephone system ran through a minefield, so did not connect to Stanley, so had been replaced with a HF radio, but this was slowly being replaced with a microwave telephone system.
The islander aircraft had replaced the beavers, but there was a problem that not all farms had a landing strip which complied, and there were problems while I was there about the state of some landing strips, I never did travel with fixed wing aircraft, all my trips were Land Rover, motorbike, or rotating wing aircraft, wokers and erics.
There was a small problem with the licence call signs, two and three letters starting with X were HF call signs, only the four letter like my VP8XBHZ was special 2 meter, and the HF call sign took presidents, so if I was in a Land Rover which a radio with call sign VP8XBYY and I heard it being called, I should answer with my call sign VP8BKM which caused some confusion.
I did have the call sign list, as I ran the QSL bureau, which was a mistake, it was not started by me, and the guy who started it left, we would get 100's of cards for people who had left the Falklands years ago, 10-year-old QSL cards, I will guess it stopped when I left?
There was a combined radio club, military and civilian, seem to remember two call-signs VP8FIR and VP8RAF, a civilian was always the named runner of the club, so they could not be out ranked.
But 2 meter was more like the local telephone service. Instead of QSL they would say "that's all right then" it did not seem to matter what had been said, so Johnny fell off a ladder would get a reply starting with "that's all right then"? And for 2 meter, the VP8 was normally dropped.
Since I would request crossing the runway using my FT290R I would have thought one could contact the islander aircraft with 2 meter. Local radio would say who was travailing anyway, even included the cat. In some islands, cats were banned. Everyone knew what everyone else was doing, which likely was the reason for the largest divorce rate per head of population in the world.
But in the main, radio wise VP8's were well-behaved. It was Hong Kong when one had to join HARTS to use the repeaters, where there was a problem with IQ zeros. The instructions were, ignore them, if I answered an IQ zero I risked loosing my access to the repeater, it could only be opened by a HARTS member, but once open, anyone could join in. Seem to remember having to fit an extra bit to the radio to open the repeater, think this was the tone card. That radio was given to my son, I got a new FT50R before leaving, but 70 cm was not permitted in Hong Kong, and one could to an extent select the call-sign you wanted. As long as no one else had it. So I was VR2ZEP could not alter the Z, but EP were my initials.