No-Release BPO - Invoice Approvals

We have invoice approvals set up on our no-release BPO's. Currently Ariba can only support one user name in this approval flow, using the Contact Name field. No groups or hierarchies can be set up for approvals on these invoices. Does anyone else have a business need for groups or hierarchies to be available for approval flow on no-release BPO invoices? We have an ER for this 1-BNTC33. Thanks.