Technical & Functional impact: What happens when a PO is rejected by supplier

Hello All,

I would like to understand what happens when a standard PO is rejected by a supplier from iSupplier Portal. I know that po_acceptances table gets updated. But would like to know the exact columns and the values (Accepted/Rejected). Our requirement is to prevent the user from creating an AP invoice if he has rejected the PO earlier. We are trying to do some due diligence if this can be taken care programmatically.  

I believe there is no change on the PO Authorization status on the PO Headers. Please confirm. 

Thanks you,

Pankaj