No, checkbox “Close” was not selected. I know this functionality and I don’t use it.
I use the “Delivery now” field (from Quantity tab in the Sales order details form to manage the delivery transactions) and when I try to post the second packing slip I choose “Delivery now” in the Parameter field group, Quantity field in the posting form. And yes, in the Deliver reminder I see 4 pcs.
In fact I do what “Dynamics user” tell me to.