Cute panto. Unless you bring your backing around to the front to do the binding, there is no reason you can't let the stitching go off the end of the quilt. I do it all the time when I am doing a panto and I often use a portion of the design at the beginning and end so I don't have noticeable areas unquilted at the edges. I am hand guided and not computer driven. Anyway, you could have save yourself a lot of unstitching if you bind with binding as the quilting going off the end of the quilt will be cut of and buried in binding. Of course this doesn't work if you bring the backing up over the top to bind a quilt.