Right you are, JJ...
All the apparently knowledgeable froods here insist that the UK's position is officially undecided and that there is an exit ramp from STOVL, maintained in place on the far side of STOVL flight testing. As far as I can tell it would mean extending Big Lizzie's phase of Harrier GR9 operations, incorporating cats on Chucky from the get-go, and building cats into the first carrier at the first refit.
On the other hand, the JSF program foams at the mouth at the very suggestion of such treachery, because there is no alternative to Dave B for the Marines. Take away the UK's B order, and the Marine jets start to look very expensive.