It's not clear to me why we need the pH of the stock to be 14, or the pH of the working solution to be about 12. I wanted to see the effect of using ascorbic acid in place of sulfite as the oxygen scavenger. (You know me.) I knew from experience that ascorbate above pH 11 or so is rotten as a developer. It fogs fiercely unless a terrible amount of bromide is there. As an antioxident, it cam take up two moleclues of oxygen for each molecule. I did one of my Q&D experiments. 1 gram of p-aminophenol, 1 gram of ascorbic acid, and roughly 15 grams of K2CO3, starting with 7 (1 tsp. I actually weighed it.) in a liter, adding bits of the carbonate until the sediment dissolved. The pH was about 10.6. My pH meter reads 9.6 with saturated borax. This was a working strength solution.
The results with FP4+ were quite good, about what would be expected from Rodinal at 1+25. 9 minutes at 69F gave a full scale negative of normal contrast.