Adding just an additional leading two seconds of silence did fix this visual glitch, thanks. Apologies, it was my first song since my return that had such an early tone switch (possibly ever? Likely, if a song's tone heavy I usually consider it a hard pass).
I poked some tips and tricks when I returned to get a refresher, but I'll take a harder look at firekorn's tutorial to make sure I've got a handle on everything that's considered common knowledge nowadays.
Karmeleaux's post in First tone change persisitently late on selecting song, fine on restarting from in-song menu was marked as the answer