This is correct - the exact semantic details are still being worked out, but you can expect to see changes soon (and apologies, I can't get into more specifics as of when).
What I can say, since it's already reflected in what versioning you see already to an extent, is that it will be a 4-point system. We can't currently display it as cleanly as we'd like yet, but as Ryan already alluded to, our current release of 18.107.5 is actually meant to be 18.1.7.5