Basic Install Base / Asset Tracking questions concerning integration with FA

Hello Gurus,

I had some questions concerning the flow between IB / Asset Tracking and Fixed Assets.

1. When an Asset Group Item is received, an Instance is created in IB / Asset Tracking, more specifically the CSI_ITEM_INSTANCES Table (there may be more tables involved but this is the one I usually refer to). If the Item is then returned to the supplier, the Instance remains in CSI and therefore in eAM. The Serial Number remains in IB / Asset Tracking and therefore in eAM as well as an Asset with the returned Serial Number.

What is the method involved to avoid this? i.e. How do we make a PO return also remove the Asset from IB / Asset Tracking / Install Base?