PRC: Generate Intercompany Invoices for a Range of Projects with Next Billing Date

Dear Team

Could you please someone explain how the PRC: Generate Intercompany Invoices for a range of Projects works in conjuction with Billing Cycle date?

For instance, we have  an intercompany Project code TSIN-TSSG, next billing date is 16th December. If we run this program on 17th December with accru thru date as 16th Dec 2015, the invoice is not generated.

However if we run the PRC : Generate Intercompany Invoices for a Single Project, the system generates the invoice for all the eligible expenditure items.

I know, Range of project process works based on billing cycle date. However i dont understant how it works. If possible please share the oracle documenation for this process.