1/4 inch off. That's not much. Personally I would finish it up as originally planned and display it on a quilt rack or use it. Without pictures its difficult to see how important that 1/4 is, are you short of backing and batting in those areas? Batting is easy to piece and add in, backing can also be pieced and probably won't be seen unless pointed out. Am interested to see what decision you make and see the finished quilt.