It varied.
There were scrap metal merchants, who bought the redundant airframes, then ripped them apart, and sold the parts to smelters, etc.
One pilot told me how some were paid £100 to fly out over the sea, and take to their parachute, letting the aircraft go.
When aircraft carriers returned through the Mediterranean, aircraft were simply rolled off the round-down.
Many were sold (or donated) to the previously-occupied countries of Norway, Holland, Belgium, France, Greece, plus Argentina, Brazil, Canada, Czechoslovakia, Denmark, India, Hongkong, Ireland, Italy, New Zealand, Poland, Portugal, Singapore, South Africa, Spain, Sweden, (and the USSR never gave any back.)
There was no hanging about, with redundant airframes, for instance finished Typhoons were wheeled out of the factory, across the airfield, and scrapped.
Others were buried in Burma, or redundant Australian mine shafts.