If you find, as I have a few too many times recently, that the excess backing gets folded over and caught underneath in your quilting, instead of unpicking the quilting, try attacking the excess fabric with a seam ripper instead. Go slowly, and slide it along right next to the quilting stitches, and you should be able to pull out the rest of the fabric from the other side. Then you don’t have to try and neatly match your quilting!
*This tip submitted by Emma@Sampaguita Quilts. Thanks, Emma!