A problem I had when fiberglassing the hull was that the saturation coat of epoxy was partially tack free. While wetting out the fiberglass I was getting wrinkles in the cloth that where very hard to get out. The fiberglass would stretch a bit on the tack free parts of the hull and not move at all on the tacky parts causing wrinkles. My thoughts are to fiberglass while the hull is either entirely tacky or entirely dry. Good luck.