@eddie-paterson 

I might be wrong but the Audit Log will only show edits to posting transactions (i.e. those that affect the accounts).  It does not save edits on non-posting items like Recurring Invoices/Templates.

In this case, the Audit Log will show edits to the saved Invoice (after the first Save) but if the Recurring Invoice Template was edited & saved before an Invoice was created from that Template you will draw a blank.

If you think the actual saved Invoice has changed - that's different & something that the Audit Log should pick up.

However!  ... There was a bug a few years ago that made a mess of Customer Addresses when re-using Templates between customers (https://quickbooks.intuit.com/learn-support/en-uk/transactions/bug-in-recurring-transactions/01/400940) .

I don't know if this ever got fixed (or even properly acknowledged) as I changed workflow to create a new template or duplicate for each new customer rather than simply changing the customer name.

Hope this helps.