From 1967 onwards it was effectively total although there were one or two a year in the Hunter (to do a ministry jet IRT) and probably 5-10 in a Dove ferrying VIPs when the comms guys needed a day off.
I completely accept that specialising in VSTOL handling issues was unusual and high value per minute stuff but my point is that what you do when airborne (and the number of sorties) is a better criteria for currency than hours in the last three months or whatever.