ebXML CPA question

[pie8ter]

I am not sure if this is the right forum for this, but here goes. I am
trying to find a way to implement the following with our ebMS.

We (say CompanyXYZ) manage CompanyA's ebXML trading with CompanyB. The
documents are exchanged directly between companyA and companyB without
going through us. I am planning for the disaster recovery for the
ebXML/ebMS. If CompanyB can't send documents to companyA or vice versa
for some reason (i.e. internet connection down, server crash, etc), we
would like to be the backup route. This means if companyB can't send
documents to companyA, companyB should send them to our backup ebMS.

Currently, the CPA for companyA and companyB specify only one
<transport /for each partner. Can we add one more transport to the
<partyinfo /of both company and have the ebMS send the document from
both companies after specified number of retries?

Thanks