Does a recurring invoice to a client regular fortnightly, uses the same invoice number or designates a new number

Welcome to the Community, @diamondtrinity.

When setting up a recurring invoice in QuickBooks Online (QBO), the system will automatically assign different invoice numbers once they're created and sent to your customers.

For more information about the process, check out this article: How to create a recurring invoice and manage recurring transactions.

Just in case, I'll add this article for future reference: Edit a recurring template.

Reach out to me in the comment section below if you have any other questions or concerns. I'm more than happy to answer them. Have a great day!