Pay on receipt AutoInvoice fails with "Acct date not in open pd" for open periods

Hi all,

I'm trying to run the the AP Pay On Receipt Auto Invoice concurrent request but it keeps rejecting invoices with the "Acct date not in open pd" error. 

As far as I can tell, the periods are open.  I've checked the Payables Periods, Purchasing periods, Inventory periods, GL periods - all open.

Is there one I'm missing?

I'm trying to run this against newly created Purchase Orders/Receipts, but it fails every time now(It used to work).

Anybody have any ideas?

FYI:

The sites are setup as Pay On Receipt and I'm calling the program as ERS.