All the lines in the sales order to be knocked off will be shown and there is a knockoff button at the bottom of screen to knockoff the sales order and create a new delivery order from it.
Sales Order Qty Edit ( Partial Knock off )
Figure 2. Partial knock off
In order to edit the line quantity, the line needs to be hold and pressed on for a few seconds and this dialog box shown above will pop up. The new quantity can be inserted into the input field.