I don’t know if this "BAS" really exists. And if it does, then its not a consultancy, rather it’s an “Advisory” business, as the accounting partnerships can’t set up consultancies now since Enron, and we wouldn’t want that.
As for what they are supposed to be doing, and where they are working – no-one is really clear. They won’t disclose any of their clients, so you’ll have to trust the ex-IBM and ex-Accenture partners that run the joint. Rather you than me, mate !!!