Frankly I am surprised this isn't an issue for others.  Why even have a parent account if the information for the parent account isn't linked to all subaccounts and subsequent updates?  I can't believe our company is the only user that doesn't have 25, 50+ subaccounts linked to a parent account that when there are updates to invoicing instructions, and billing emails and addresses to the parent account that information needs to also be changed for each subaccount.