The Contract Billing Preference allows you to customize Contract Billing options with two tabs: CheckList and Other.
In the CheckList tab, the "Include Recurring Contract Charges in Production by Default" checkbox can be used to count all Contract Billing charges towards production reports as a default. You can override this setting for all Billing Contacts by unchecking this preference checkbox. To manually override the setting per Billing Contract, uncheck the "Report Recurring Charges As Production" checkbox in the Contract Billing Window of the contract that should not count towards production.
Within the Other tab of the Contract Billing Preference panel, you can set the number of days prior to the due date in which MacPractice should post contract charges automatically with the "Automatically Post Contract Charge _ Days Before Due Date." option. This option is "0" by default.