the Seasprite as I understand it was orginally selected because it had a footprint small enough to operate from the proposed OPC vessel (later cancelled).
Entirely correct. Once these ships were cancelled the Seasprite was not required.
Those 'senior military' somebody was mouthing about wanted Seahawks, they got (well they haven't) Seasprites. The Seahawk fits in the hangar, and on the recovery thingie (which the Seasprite DOESN'T!) I think the problem is bureaucrats not listening to the "I want THAT one" part of the military.