Out of the Wood Oven...Again

Different dough hydration will determine how fast you do folding, resting and shaping.  You can also cut the dough anytime with a quick sharp knife and look at the dough and observe how the gas is forming inside the loaf.  (Slap it back together after looking cut edges back together.)  

Look at the dough between the bubbles to see how gas is distributed.  Large bubbles surrounded by dense crumb is a sign that gas is collecting. Your experience with the estimated fermenting time of your starter and familiarity with the recipe will let you know if it is under proofed (collection of gas due to early stages of fermentation)  or over proofed (collection of gas due to gluten structure breaking down.)   

Large bubbles with superfine tiny round bubbles, needs another fold to collapse the large bubbles (I can feel them under the surface) and redistribute food and temperature while tightening up the gluten matrix and outer skin.  It is common to jump right away into folding before the dough has fermented enough to warrant it.  This tends to happen more often with sourdoughs with strictly planned recipes not taking into account variations in wild starters.  Another rise will even out the crumb bubbles (still with assorted sizes but not so extreme)  as the dough relaxes and fermentation speeds up.  If a finer crumb is desired, more folding can be done with a shorter final proof.  Long periods between folds usually results in more variety of gas bubble sizes providing your recipe flour allows for such happenings.  If watching the dough on a flat surface, folding is needed at ever shortening intervals to maintain shape as the dough degrades with time.  

Gluten structures need to be developed in the first half of the dough's time line and delicate ones need protecting.  That the just of it.

Large bubbles with strange amoeba shapes smaller bubbles tend to be over-proofed or quickly getting there and the bubbles are leaking air into larger gas pockets higher up in the crumb near to the top crust.  Dense crumb below these large bubbles or in a line about half an inch or 1 cm above the lower crust are also evidence of over-proofing.

As mentioned before, you can slice into the dough and check on gas/crumb development and it is a great teacher.  When you are looking at that cut crumb, take the time to do more observation of the dough, how it feels, size to weight, sponginess, how easy it moves as you roll it in your hand, aroma.  Before cutting, try to feel the inside getting a picture of it in your mind by the feel of the outside of the dough.  Cut to confirm your image.  This helps you paint the picture for your memory and improve hand-mind coordination.  

Later, compare the baked crumb with your observations and time spent rising.  If you have seasons, don't forget to note the temperatures and humidity.  Many of these factors you are already noticing and calculating in your head as you mix dough and wait on the oven making small adjustments to speed up or slow down the rising.   

By the way, you have great dough development, just the thought that large bubbles can happen in WW is an eye opener for many!  The distribution of the bubbles is what makes me think an extra fold would be good.  The bubbles appear off to one side predominantly and on the bottom not all clumped at the top of the loaf (as what would happen with over-proofing.)  The other option would be if the starter was slowing down suddenly and the method/timing remained the same as previous good bakes.  This would be a sign that the starter yeast needed to ferment/multiply longer before shaping.

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