When you create a new Account, it will, by default, have Invoice Settings that match your Company defaults (Settings > Company Information > Accounting). These settings can be customized for each individual Account. Navigate to a Review Account overlay then click Edit. You can change the billing Terms from the "Billing Information" tab:
This will determine how soon the Account's Invoices show as "Past Due". If this is set to "Due on receipt" then Invoices will show as "Past Due" as soon as they are generated unless the Invoice date is in the future. To edit the Invoice Frequency or the Invoice Delivery Method, go to the "Invoice Preferences tab:
If When to Invoice is set to "Monthly" then all Jobs completed in a calendar month will appear on a single Invoice at the end of the month. If this is set to "Daily" then an Invoice will be generated each time a Job is completed.
These settings will appear here on Invoices:
Additionally, you can change the AR Account from the Company default as well. If you want to change this, it can only be done on an Invoice by Invoice basis by clicking Edit from the Review Invoice overlay. This field does not pull into any pre-made reports in SA but it can be a field used in a custom analysis. It may affect your general ledger if you sync with QuickBooks.