Unexpected and incorrect MCTruthAndBkgCat behaviour

When using MCTruthAndBkgCat in master on a sample produced in Moore there is unexpected and incorrect behaviour.

Running on an Lb2JpsiLambda sample (15144103), the MC truth information (TRUEID etc) for the reconstructed Lb appears identical to the reconstructed Jpsi.

When running over the same inputs and scripts with lb-run DaVinci/latest ... the MC truth information appears as expected.

Example scripts and files can be found at /eos/user/i/isanders/public_lhcb/MCBkgCatBug