Closing PO prior to Inventory close

Hi,

We always follow the process of closing Inventory prior to Purchasing close. But we would now like to change the process and would like to close Purchasing first. Can anyone please let us know, if there is any implications of this. Will you be able to let us know :

    Is there a risk if PO is closed prior to Inventory close?

    If so, is the risk limited to the receipts passed subsequent to PO close?

    Is there a system functionality which can restrict buyers from passing receipts in the system on specified days?

    Any other implication

- Cesar