Batik Jelly Roll Quilt, concerned about colors bleeding
I am just about done piecing my quilt made from a jelly roll of batiks. Because it was a jelly roll, I did not prewash the fabric. The lady at my LQS knows I don't prewash fabrics, but recommends it for batiks "because they are dyed from the outside". So . . . my question is, should I try to soak the top in something before the quilt is sandwiched? Or wait until its done and do it? Or both? The fabric for the backing is also batik.
The quilt top has a gold (non batik) sashing. Appreciate all the expert advice.