A new event has been developed that will trigger after an order line item's invoice is posted. This means that an order's invoice has been posted via Customer Order Processing > Processing > Post Invoices. The event is called "ILIPOSTD" (Invoice Line Item Posted) and is found in IMITMFIL files in Inventory Management. 

When this event is active for a specified item, a notification will be sent to anyone subscribed to the event if that item's invoice is posted.

To set up this event, you need to make it active for an item. Go to Inventory Management > Maintenance > Item File.

Bring up an item with Change and click the lightning bolt icon.

In the Event Request window, press F5 to add a new event via Event File Search. Search for the event with the following fields: "Program: CP0305, Type: ILIPOSTD, Detail IMITMFIL, Description: Item Line Item Posted." Press Enter.

Proceed to select what kind of features, messages, or filters the event should have. When you are done, click Save.

You now have an attribute associated with this item. Whenever you use Post Invoices in COP and an invoice containing this item is posted, the event will trigger and notify people accordingly.