I bought a boule of sourdough at the grocery that was labelled:

"Goldminer California Sourdough"
"Baked Fresh Daily"

They give a website:

www.californiagoldminer.com

but it is not helpful to the home baker.

On the package they speak about "California Goldminer relies on the
24-hour fermentation process ..."

What "24-hour fermentation process"?

I have seen extented fermentation processes, but I do not recall any
that went as long as 24 hours.

Do you do this 24-hour fermentation process in the refrigerator or at
room temperature (75-80F)?

How many times and when do you punch down - when it doubles?

How much of that 24-hour period is used for the final rise before
baking - or is that a separate time period?

The bread was indeed quite sour which I suppose is the result of a
long fermentation.