@Lisalewisgale1 

Try it and see.  Not sure why would you change the bill date to March.  Sounds odd.  All you need to do is to assign prepaid inventory (no items) to the March bill or payment.  Then, move that prepaid inventory to a vendor credit (A/P) when you receive the inventory in July with a journal entry (debit A/P, credit Prepaid Inventory).  Then, receive the items on an item receipt with a bill and apply the vendor credit created by the journal entry to the bill.  That will record everything accurately.