Hello! Thought I'd finally introduce myself after six months or so of lurking.
I just brewed my fifth batch of the year (EdWort's Haus Pale!) and this site has been very helpful in my trials and tribulations in learning the art of the homebrew. I have some successes, and some near failures...
I ran into the exact same issue when I brewed this recipe as a partial mash a couple of months ago. I even ended up with the same OG as you!
At first I thought it might have been because I have a small-ish nylon bag and the grains were too compacted to circulate in the mash which limited...