All purpose flour boule

So I’ve just finished my stock of bread flour???, and I can’t find any at my local supermarkets, so I tried making an all purpose sourdough with some spelt (~ 15%). What do you guys think?  Taste wise: it was not that sour , but I think that’s because it was a one day bakes. Next time, I’ll retard it over night in the fridge and I might experiment with using a stiff starter. Do you think that would bump up the flavor?

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