Until BACX pulled the ABZ/BRS route last year they (and before them Brymon) operated it with DH 8s via NCL, with one rotation via MAN at various times, but the MAN route never seemed to succeed, partly I suspect because of its lunchtime timing (no good for business pax going to MAN from BRS or vice versa).
easyJet has taken over the BRS-NCL route and BACX is to withdraw from it in October. Air Southwest has announced a new BRS-MAN route (3 x daily with DH 8s) so MAN and NCL appear to be 'non starters' for an intermediate stop.
Do Eastern already servce LBA from ABZ? If not that could prove a possibility for an intermediate stop. Last year BACX operated BRS-LBA with J 41s, but the route was not given enough time to settle down before BA got rid of their 41s to Eastern and chopped the route.
ABZ-BRS is certainly a long way in a J 41, but much better than no route at all!