Is there a SOAP/Web service to make bulk updates to the Contract Billing tab attributes?

Summary

Is there a SOAP/Web service to make bulk updates to the Contract Billing tab attributes?

Content

Hi Everyone

Is there a SOAP/Web service to make bulk updates to the Contract Billing tab attributes?

I have multiple requirements to update 800 existing contracts (converting from Legacy systems) to change the following:

1. Bill Plan - Invoice Method
2. Revenue Plan - Revenue Method
3. Generated Invoice Status
4. Invoice Grouping

All of them are in the Billing tab of the Contract where I need to make the updates in my contracts.
Raised an SR with Oracle Support seeking guidance and I am advised there is no SOAP/Web service to make such updates. This will leave me to make all these updates manually to each and every contract which is laborious.