v126.96.36.199910, W10, Focusrite Pro 40, newer (6 mos) mostly state-of-the-art custom PC build.
Suddenly, today the notes just don't render correctly after an attempted midi edit. The audio comes in early now.
The out of synch audio, once transformed back to a midi/instrument track, still shows this section of midi notes where they were originally placed correctly on the edit>piano roll grid.
Upon closing and re-opening the song without a save. The bounced audio returns back to where it was intended, but can't be edited without going out of synch again upon any attempt to transform>bounce the instrument track.
I tested other midi instrument tracks in the same song. They are not being affected in the same way.
This affected intro section is on a separate midi take from the rest of the instrument track in the song.