For the life of me, I can't find a definition of what the "A" indicator on Rockshox fork model numbers means. (Specifically, I'm looking at Reba RL 100mm tapered 29" forks, FWIW.) It looked like maybe "A6" meant 9mm QR, but I've seen "A8" forks listed variously as 15x100 and 15x110, so it seems that line of reasoning is out. Is it a year indicator? (And if so, why for the Love of Pete would an "A8" be a 2019 fork?? :-) Can someone clue me in, please? (I'm sure this is findable information somewhere, but I have failed...)