Non homogenous sourdough crumb

So this was a 80% hydration loaf with 20%ww/80% bread flour, and at 20% inoculation and 2% salt. Bulk fermented at about 76F for around 5.5h, doing 1 s&f, 1 lamination, and 3 coils. Preshaped and shaped and retarded 20h at around 40F. Baked at 425F covered 25 min, and at 400F convection uncovered.

What I'm curious about is the present of these dense bands amongst the more open crumb. I see decent oven spring and a nicely browned crust. However crumb is also a little gummy. Anyonehas any insights into what the issue I'd withhe uneven crumb? Thanks!

Well, I believe many wouldn't see an issue here. Uneven distribution of different sized holes is supposed to be a good thing - and you have a very good example of that. What exactly were you looking for in the crumb?

I think it's possible that some of the bigger holes are from air trapped during folding/lamination rather than fermentation. Just my guess based on what i think i see as layers of folded dough and the big bubbles are in between those. during folding try to pop any large pockets of gas.

Shaping may be a little tight. Be gentle. You didn’t get much spring on one side of your scoring. Note the tighter arc.