Let's not forget that MRA4 was cancelled to save £2 bn over 10 years in support costs. Nine MRA4s was often said to be inadequate, so the minimum fleet of P8s with half the range/endurance must be around 20, so it's looking like an investment of knocking on £3 bn to buy the aircraft, set up the base/infrastructure, provision spares, train the crews etc etc. As Biggus said, where does the money come from? .....anyway the Conservatives have already said the gap can be covered by "other assets". Yes, the HCDC talks a lot of sense, but an appeal by one member for a stay of execution on MRA4, while the HCDC reviewed the decision was roundly rejected by Cameron.
EG