Will as you mentioned, they are a contract brewery that does some of their own stuff on the side... they likely can't say much about who they produce for if they can at all due to contracts. I know from being in the industry that they have a bit of turnover or constantly expanding (rather unlikely to the frequency in this context) based on job postings. I haven't ever heard either great or good things about them... this is typically a good thing in contract brewery situations as the brand doesn't normally want outsiders to know they are in a contract position for the extra capacity. Most breweries would rather have everything in house unless necessary and then only with those they trust.
If looking to do business with them, check out the published tap room draft list and contact those breweries that are featured, and being poured in their taproom for references as well as ask Beltway to provide references and check with them.