Backorder: status pending invoicing

Hello, I am quite new user of Navision.

really often I have backorders with status Pending invoicing.

For example, the order left the warehouse and there is a registered packing list in the system, but some of the items were not available and in orders there is back order with status Pending invoicing.

What is going to happen if I will delete it?

the order (items) that previously left the warehouse will be invoiced (there is the packing list) or everything, the order and back order will be deleted because of removing back order pending to invoice?

Hope I explained it in clear way.

Thank you.