I wouldn't want anyone not to question Typhoon (especially Tranche 3), as no sacred cow should be viewed as being sacrosanct in these difficult times, and any means of saving money should be assessed on its merits.
Unless we do so, we'll have a bizarre force mix, of the Brass's favoured toys (CVF, Typhoon, FRES) and the odd bits and pieces that win support on nostalgic grounds, or because they are well known to the Public (The Reds, Dartmouth, the Kings Troop RHA), while the Canberra PR9 and Nimrod R1 (for example) will go unreplaced.
In fact, any informed debate would VERY quickly conclude that Typhoon is:
a) Needed, both for UK AD and as a flexible, deployable, cost effective A-G platform (It's clear that with a modest resurgence in Russian air activity, four AD squadrons is barely enough for UK AD, and three extra squadrons to support expeditionary requirements, etc, is hardly controversial, surely?). Even with seven frontline Typhoon squadrons, we'd have fewer Typhoon units than those they're supposed to replace.
b) Largely paid for already, with cancellation penalties making cancellation financially unattractive
as OA says.
The only point I'd take issue with is the claim that "we all know" that 232 is 'too many'. 232 is meant to sustain a fleet of 137 through to the planned OSD (a bloody long way away when the figure was dreamed up, and likely to slip to the right, quite rightly, with no rapid development in the threat). 137 aircraft was supposed to support seven frontline squadrons, with 15 aircraft each, (plus an in-use reserve each), four aircraft in the Falklands, an OCU with 24 jets (plus two in-use reserves), and an OEU with four jets.
Seven frontline Typhoon squadrons, to replace three Jag and five Tornado F3 units (and some of the dwindling GR4 fleet) does not seem to me to be in any way excessive.