The dough was kept close to 76F throughout mixing and fermentation.
Mix starter and water. Add seeds and oil, mix. Add flours and salt, mix just until flour is wet, rest 1 hour, fold 3x at 30 min intervals. Let rise until near doubled (about 2 hours). Shape, put in triangle brotform, and deposit in fridge for overnight. Bake at 500->460F (after a half-hour out of fridge) under cover for first 20 minutes. Let rest in oven for 10 minutes after bake.