I have already bought a BB control board for s19 will it work for my miner?
well according to this link no
https://altairtech.io/product/bitmain-antminer-s19j-control-board/but this company does have a rep here on the forum. and they will answer the question you are asking on their website.
I have interchanged some s19 controllers and I can tell you they don’t always work when they say they will.
and sometimes they work when they say they won’t.