Bletchley is in Buckinghamshire, in the South East region.
Yah, but you seem to be missing the point I was trying to get across in my last point - I think that there is nowhere in the East Midlands region as you've defined it that fits your clues. I've therefore gone for somewhere in the valid area of the East Midlands Rover.
I've found the following stations in the East Midlands Rover area, which covers the entirety of the East Midlands (except between Disley and Buxton), and a little bit more, that are also members of routing point groups
Bletchley
Milton Keynes Central - Served by Virgin
Belper - Served by East Midlands Trains
Derby - Served by East Midlands Trains
Duffield - Served by East Midlands Trains
Long Eaton - Served by East Midlands Trains
Peartree - Served by East Midlands Trains
Spondon - Served by East Midlands Trains
Barrow-upon-Soar - Served by East Midlands Trains
Loughborough - Served by East Midlands Trains
Sileby - Served by East Midlands Trains
Newark Castle - Served by East Midlands Trains
Newark North Gate - Served by East Midlands Trains
Attenborough - Served by East Midlands Trains
Beeston - Served by East Midlands Trains
Nottingham - Served by East Midlands Trains
Dore and Totley - Served by East Midlands Trains
Sheffield - Served by East Midlands Trains
Norton Bridge
Stafford - Served by Virgin.
Norton Bridge and Bletchley are not in the East Midlands area as you've defined it. I therefore think that you've given a duff set of clues.