Truth matching bug: particles incorrectly matching to electrons

I think LHCb!4453 (merged) may have caused a new truth matching bug incorrectly matching tracks to electrons (not yet confirmed).

If I compare master with an older version (Moore v54r22p6) for 1000 events in the same sample, we now have a sudden increase in the number of tracks truth matched as electron (by a factor of more than 13). The effect is has a charge asymmetry, in that the increase only appears to be for e- and not e+. Most of these seem to be coming from tracks previously matched to pions, but not exclusively.

I only notice because I am working on the Calo PID for T tracks, and the long track ECALPIDE distribution looks very wrong, with almost all "true electron" long tracks having a very low score, meaning this is probably a truth matching error and these are not really electrons. (The sample is a BSM B\to KH'(\to\mu\mu) so the electrons are not signal but coming from the rest of the event, hence the low stats.)

The issue only seems have a small effect on T tracks, if any, so it is only Longs (I didn't check Downstream).