Indeed it seems it was. The J was designed for cruise in the low-to-mid 30s, where it has outrageous fuel efficiency and TAS (at least that's how it was sold to the RAF). It gets from 0-FL280 very rapidly, where it sits burning fuel at a rate not that much less than the K, severely limiting the range that can be achieved in a crew day.
Yet another thing that shows up poor planning in procurement - they could have anticipated requiring RVSM clearance alot sooner. It's not as if major modification is required. Sad that, 8 years on from introduction, we are only now approaching where we should have been from the start.
The J procurement and introduction to service should be made into a case study of how not to do it - there's no doubt the aircraft is a massive leap forward in capability, sadly hamstrung initially by piss-poor back-office support.
Incidentally, what are the requirements for MNPS? Does the '10 have 3 nav systems?