Bicester Stations - Why have trains been diverted from Oxford Parkway? Why can't you run the same level of service from Bicester North as you did previously?

There are still only two tracks to accomodate all trains between Birmingham, Oxford Parkway and London Marylebone. We have however lengthened the platforms at Bicester North during 2015 and purchased 5 new 2 car trains that we run longer.