Accurate Cash forecast when using expense PO's

  We are creating just Expense PO's and there is not an item number involved, therefore shipment information is not available at the PO.

The problem to solve here is: how to generate an accurate Cash Forecast when we create Expense purchase orders and they are controlled by amount and date?

Also to note: We are not currently using Contract PO's but will consider it.

 

From Oracle Guide: When Cash Management collects the source data for a forecast , it includes source transactions whose cash activity date falls within the days or period ranges you defined. Cash Management searches for a valid date in the sequence indicated, using the first date it finds. Cash Management adds the lead time to dates, except for GL Budgets and GL Encumbrances.