Hi Wigglewaggle.
Thanks for getting in touch with the Community.
I've just been testing this out with my Self Employed account to see if this is possible but from what i can see the only way would be to send the invoice. I suppose one option would be enter an invalid email address or your own email address for the older invoices so that the older invoices are emailed to yourself instead of your customers.
I will be sure to submit this as feedback for the Self Employed product as I know this is something we are able to do with the small business products so i will see if this is something we can get added to the Self Employed product.
If there is anything else I can help with, please let me know. :)
