Please just stop and fix the problem. It's been four years and every knucklehead support moderateor that jumps on here offers no solution.  I've been setting up invoices and they have been sending in the same order that I set them up.  Now they are getting re-ordered in the PDF.  I have not seen this until now.  Furthermore, they are not ordered by date on the PDF.  I am seeing them in random date order.