In total, the BB's probably did about a dozen trips in 'private ownership' between late 1999 and say 2002.
The trips ceased due to changes in insurance premiums to run pax trains during the insurance crisis of 2002/03 - i.e. the $ didnt stack up for what was basically a train spanking exercise, so the operations were cut - also the trips were run by GNR as I understand, who went into receivership in 2003 (I think).
The picture link above was the ONLY time the BB's connected with SRHR, essentially as an exercise to prove it could be done - the insurance stuff hacked up pretty soon after this trip. They NEVER ran into MBJ platform - there were steps and walk downs to get between the bluebird and steamranger cars.
The cars ended up owing CFCLA a shirt load, so the only way to redeem the $ tied up in them was to make them into crew cars.