What's the current UE of a Typhoon Sqn? I'm assuming about 16, if so, bearing in mind that at one point a UE of 10 was established for sqns in Germany in the 1970s it should be easy enough to simply move airframes around to leave about a dozen each among six units and some spares. As for airframe hours, are they being used up at a comparative high rate. Recalling the amount of movement, again, during the '70s and 80s... I can't see airframe fatigue being anything to give concern.
FB