Custom capabilities accumulation

Do custom capabilities accumulate?

eg - a subscription has a,b,c custom capabilities
the subscriber then subscribes to d,e,f ccap the following month

do they now have a,b,c,d,e,f ccap?

Thanks

It seems so. There does not seem to be any process to remove/replace them. If a subscription ends, it might remove EVERYTHING, including the ccaps that are not associated with the membership (like a buy now).