-=item billing_balance - the customer's balance at the time the invoice was
-generated (not including charges on this invoice)
-
-=item previous_balance - the billing_balance of this customer's previous
-invoice plus the charges on that invoice
-
-=back
-
-Deprecated
+=item billing_balance - the customer's balance immediately before generating
+this invoice. DEPRECATED. Use the L<FS::cust_main/balance_date> method
+to determine the customer's balance at a specific time.