Using the batch report Create Recurring Sales Invoices, setting the Order Date and Posting Date, invoices will be generated against the same customer multiple times over if you set the same dates. There is no control to restrict that certain customers have either already been invoiced for that date and there is no ability to set the recurring frequency at which the customer should be invoiced.

It would be good as a base to have a warning that a customer has already been invoiced at that date and to hold a value against the recurring sales line for when the invoice was last created/posted so to only generate further invoices for that customer from that date onwards. Enhancing this further to have a recurring frequency on the Customer's Recurring Sales Lines would be more beneficial so that periodical invoices will be generated via the report.