It's certainly possible that the MRA4s could go across the RN - because the cost of providing a sustained ASW cover that even a comparatively tiny force of MRA4s could with other assets (ie FF/DD, Merlin) would likely be much higher. Similarly, passing the SH to the AAC would give the illusion of RAF savings without actually cutting capability. I don't have the numbers, but I suspect that the small difference in AAC SNCO vs RAF FOFL capitation rates would actually make real saving over the next decade if SH went to the AAC.
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