@DBhomebrew Would be interesting to know if I'm correct, since I am by no means a Brett expert. Just wanted to mention the ale as something that tasted far more complex than the general commercial ale. I cannot believe Nottingham is the original strain, is that first hand information?
The beer is astonishingly complex and has a slight sour note. Not necessarily horse blanket, so there might be other microorganisms involved. But old oak has always been the home for Brettanomyces, no matter if Memel or otherwise. But 2% Black Malt and Nottingham would never create a beer like that. Something special has to happen on the yeast side.