Henry,
Un-sewing is part of the process. If you don't have a seam ripper get one. It is extremely valuable! Un-sewing is also called 'frogging!' "Rip-it, rip-it, rip-it!" and you can fix most anything at all!
Your other option is to call it a design decision! "You did that way on purpose!" Oh, yes. No messing up big time in quilting. They're just design options!