Here’s a few pro-Bono organizations that help with discharge upgrades! : Veterans

I’m about to graduate law school and am an Army Vet. There are a lot of law schools that have clinics that specialize in veteran issues including discharge upgrades. A quick google search will give you the full list but Yale and Hofstra in the northeast both have great clinics. They typically only take on cases of individuals who can’t or would struggle to retain an attorney at a firm. Also, check out the veterans consortium, they do great work!