Patti, I think I'd just add a strip and go with it. No sense wasting all that time you put into it to do it all over again. It all depends on who fussy you are. We have put a lot of time into these quilts, haven't we?
Edit - Duh! I just re-read Laesley's entire post - shoulda done it before. Forget what I said above. She's "righter" than I was! I wasn't thinking. Of course, your quilting design will be out of place if you add a piece to the bottom or side or anywhere. Do overs! JMHO