First you're talking BATIK!! I ALWAYS wash my Batiks first (sometimes they need to be washed more than once), they have been known to run, run, run.
Also you will have shrinkage of your backing, so before I would try to cut it again I would wash and dry it.
Also if you're sending it out to a LA, how much overhang do they want? And then are you pulling the backing to the front for binding or are you adding a different binding?
Good luck