Safety stock not consumed on purch order

Hi

System : AX2012R3

1) I have an item, TestItem, with a safety stock of 1000. I have zero in the warehouse.

2) A purchase order(PO1) is made for 2000, arriving on 20 jan.

3) A sales  order (SO1) is made for 500 to be shipped on the 20 jan. The items are consumed on PO1.

4) A new sales order (SO2) is made for 1000. 500 i consumed on PO1, 500 on a new Purchase order see below.

5) Master plan creates a new purchase order(PO2) for the 500 pieces on SO2 arriving on 25 jan.

6. Sales SO2 now has a shipping date 25 jan. (from PO2). 500 items pegged from SO1 and 500 items pegged from SO2.

7. PO1 arrives on the 20 jan. 

8. Masterplan consumes 500 from safety stock for SO2 and SO2 gets a new shipping date, 20 jan.

Question:

Is it possible to consume safety stock on PO1 for SO2 before it is recived?