I did mean Layer 7. I've been calling it Layer 8 for a long time now, lmao. Not sure how that got mixed up and made permanent.

There are alternative/extended models out there. Perhaps you ran into one of those?

Entirely possible; I've worked in the intersection of Software Engineer and Systems Engineer most of my career, so that leads me to think maybe I'm prioritizing some of the stuff I learn and that older things I've learned have degraded. I say that mainly because I learned the OSI model very early on in my career.