A user with Sales access can edit a deal to initiate the billing to be performed at an earlier date than the standard system settings. For example, the standard system setting for a deal that is set with a 50/50 billing model is to initiate billing 30 days in advance of the print date, but you can override this from deal to deal to improve cash flow.
Go to Sales & CRM and bring up the deal you want to change the billing date for.
Go to the last tab named Billing schedule.
Select the line you want to change by clicking on it, then on the left hand side, click Edit.
Change the date for Earliest billing date to the date when you want the billing to be initiated, then on the left hand side, click Update.
Click Save and Close at the bottom right of the Deal form.
Now, when you go to Finance >>> Billing >>> Deals to bill, this deal will shop up so you can initiate the billing per the normal billing process.