Currently on the system, the revenue is recognized upon invoicing of sales orders, However based on the IFRS 15 Standard operating procedure stated here:
https://www.iasplus.com/en/standards/ifrs/ifrs15
which states that Revenue should be recognized as soon as entity satisfies a performance obligation.
the delay in the revenue recognition is desired.
currently the packing slip is submitted at the point of delivery, and minuted upon by customer to confirm receipt and satisfactory conditions, however, the customer would require the invoice number also at the point of delivery.

However, once invoiced, the revenue is recognized before delivery is confirmed and satisfactory conditions are reconciled.