Mix starter, water, sugar, salt, flour, zest. Rest 30 mins.

Do 1 stretch fold.

30 minutes later, laminate dough and add blueberries.

30 mins later do one coil fold then bulk ferment until doubled.

Preshape and rest 20 mins.

Final shaping and cold proof or just pop in freezer 20 mins if baking same day.

Preheat oven 450.

Add bread, covered and immediately lower to 425. Bake 25 mins.

Uncover, lower to 400 and I baked 20 mins more.