Hi Scot!
Thanks for sharing this. I think what’s happening is that you do have enough posts for a page 2, but the assignment rules are not triggering to keep that layout when you navigate there. I was able to reproduce this and made some adjustments to how the rules are processed. I’ve also cleaned up the labeling a bit. It will always show “Blog” first, and that will be treated differently than "All Archives ".
We’re going to push a patch today, so give that a shot once it is out. Thank you so much!