JN,
Surely the RAF will have been training up sufficient WSOps to continue. And as the procurement cycle is likely to be a lengthy process this should give the planners an idea of how many personnel with the correct training will be required. However, if the critical experienced personnel all PVR then 51 are screwed and they will have to make do with a lesser experience level to do the same job (sound familiar?
).
Worst case is that the government decides that ELINT is too expensive for a nation our size and takes a 'capability gap' whilst hanging onto the skirts of USAF RJ's.