Showing backordered items (remaining open quantities) on invoice

I would like to show items that are backordered on an invoice created within Business One. We can show partial shipments, but not items that are backordered (or are remaining open quantities). To give an example, if a customer ordered Part A and Part B, but we are only shipping Part A, we would like Part B to show up on the invoice as backordered. Currently, when we delete the item line of the "part" (Part B) that will not be shipped, we have not found a way that the "part" can be referenced on the invoice.

Best regards,

Hal Filter