Hi Daryl:
Do you have a client who is requesting this integration? If so, can you share the company name with me via DM?
The Ariba On-Premise team advised that upgrading to 9r2 requires far less effort than the 9r1 upgrade required. If a customer wants to use 9r2 upstream integrated with downstream, it's required that both applications are updated to 9r2.
Regards,
Debbie Curtis-Magley
Ariba Exchange Community Manager