I believe that Invoices 8.0 will be available in the next 3 to 4 months but there is something that you can do in the meantime.

You can export the Archived batch into Excel format and then sort it on Customer Code or Name. Sort as follows:
Customer Code (or name) - Ascending
New Detail - Descending

When you save the spreadsheet, leave it in Excel 2.1 format just in case.

Then import the file either directly into an new Invoice batch or back into a new Archives batch.