When I started flying Puma in 1971 the MAW was 6,400 kgs. and the gearbox life was 900 hrs. Around 1973 the AUW was increased to 6,700 kgs and at the same time they initiated the CAAP Programme. (Component advanced ageing programme)
The was a programme to fly selected aircraft; two RAF and four French Army, one hundred hours a month each with the gearboxes stripped every two hundred hours so as to extend the fleet's life to 1800hrs.
This was successful so the Puma entered the civilian market. I flew the 'J' model with plastic blades up to 7.400 kgs.