Delete Item from Promotion on Order with API script

In the application UI you can select the Edit Promotion menu option on a Modify order and then delete a customizable product from a root line item associated with the promotion. The root line item and all the child items get a Delete action code with ABO enabled.

 

Can you delete a root line item from a promotion with a custom script using an API method?

 

The method “DeleteItem” is invoked and is built into the class code for the vanilla applet “ISS Promotion Edit UI Detail List Applet”. There does not appear to be a method “DeleteItem” for a business service that is documented. Disconnecting the root asset is not relevant as there is an existing process that is generating an existing Modify order.