On the large format forum there has also been some discussion on it. Or perhaps that was only about unexpectedly low activity of ready-bought pyrocat. I can't comment; I haven't experienced it myself with my DIY chemistry. The formula doesn't seem very prone to sudden death looking at its chemistry; perhaps the vitamin C versions are more likely to exhibit this, analogous to XTOL.
Now that I purchased Pyrocat-HD in Gylcol Film Developer I am not finding development time, temperature and film speed information for Kodak Tri-X 400 in 120, Ilford Delta 3200 in 120, Rollei Infrared 400 in 120. References? Sources? Recommendations? Please.
After having 'tried' them all.... I'm now 'stuck' with Pyrocat HD for all my sheet film developing. There is minimal to no obvious 'stain'
But I am sure I'm getting 'sharper grain'. (I also use only BTZS tubes and 'rotary' development.. no more hangers in tank or tray development that I had been using for some 40+ years
I mix mine from 'scratch' using a somewhat archaic three-beam balance' and distilled water
Since I 'found' Pyrocat HD, (about 10 or so years ago) it is now the ONLY film developer 'allowed' in my darkroom.. for any and ALL large format BW negatives (developed in BTZS tubes).
Might I suggest that you check out Dr. Sandy KIng's web site for all the information you are likely to 'need". I use an archaic three-beam balance for measuring out the required amount of 'raw chemical' for dissolving in distilled water.