Modify purchase order line schedule with OIC

Summary:

I have a new project where there is a requirement to change the "Promised Delivery Date" for a purchase order line in Oracle ERP Cloud. That field appears to be on the purchase order line schedule. We are familiar with OIC but do not have a lot of functional knowledge of the ERP REST APIs or SOAP services. I'm looking for any good articles or online guides that might explain the most straightforward way to modify an existing purchase order programmatically from start to finish. Any pointers or advice would be greatly appreciated.

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