Something as minor as this might have been captured somewhere in the SDN blogs. But I just wanted to ensure folks get an easy way to identify this, if they run across the same issue again.
This is a pretty common function module within SAP that is used to create quotes in ECC systems.
It has got an extensive set of import parameters that serve a wide range of functionality. The trouble is, identifying the right ones.
One functionality needed was overwriting the default customer master address with an address that comes in from the source that makes this BAPI call.
In any transaction, the standard by defaults picks up the default address that is present in the customer master.
The quotation partners contain all the partner information that is to be populated into the quotes.
Within this table, there is a field for linking the additional address details that are to be provided.
This establishes the link to the table PARTNERADDRESSES in which you can pass the additional address and email details and it can update the addresses in the quote that gets created.
We just need to ensure the ADDR_NO field contains the same number. Hope this info helps to perform the same kind of update for other document types also.