Hairpin jumps to another system's hairpin during drag/arrows with unknown details

I'm not sharing the score here for personal reasons, but know that there is something fishy with it. Thing is, I can't reproduce the error on a fresh score, so it's something interrelated with previous elements of a score some how more than likely. This probably isn't of much help, but I wanted to log the fact that it exists, even if it's rare (rare in that I've only experienced it in one occurrence). And it didn't happen with [ctrl+right/left] but only regular arrows, and it also happened with mouse dragging.

Maybe it has something to do with the new code having to do with the jumping of the nodes when dragging? As to whatever might be allowing it to jump to a previous hairpin in another system is beyond me at the moment.

For now, this is just an appeal to the guys who implemented those changes to maybe see if anything subtle might be happening incorrectly. Otherwise, the new 3.5 changes are definitely a decent addendum to MS's functionality: