BAPI_SALESORDER_CHANGE

I was requested a program that updates Sales Order partners. I did this using BAPI_SALESORDER_CHANGE and the PARTNERCHANGES table. It works fine in DEV but in QA and later in PRD, the number of Sales Orders being updated can be huge. Foreground processing leads to time-outs. BAPIs aren't known for speedy updates but does anyone have any tips/techniques for speeding these things up?