Invoicing Project Events where mor than one agreement exists that Funds that Project

We have the following situation within Oracle Project Billing...

1.  We have created two seperate Agreements; A1 and A2 that both Fund the same project; P1.  Both agreements are for 1000$ and 1500$ respectively.  Both events are set at Hard Limit for Invoicing.

2.  We created an Event for Project P1 that is for 500$.

3.  When  we ran the invoicing process the Event was assigned to Agreement A2.

4.  We then realized that Agreement A2 should never have funded project P1.

The questions are as follows...

1.  How doesthe invoicing process determine the order to assign the Events to the various Agreements to during billing.  I.E. how does it know to use A2 first before A1?