How to prevent Change Order documents auto-sourcing from BPA?

Summary:

We have enabled the feature to "Disable Automatic Sourcing from Requisition Line" and this prevents the Purchase Order from auto sourcing from the BPA.

However, when this PO is changed the Change Order document is sourcing from the Blanket Agreement again. We want to prevent this from happening.

Is this possible?

Content (required):

The current workaround is Buyer manually clears the auto-populated "source agreement" fields at the line level.

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