beta-D-galactofuranosyl-(1->5)-beta-D-galactofuranosyl-(1->4)-alpha-L-rhamnosyl-(1->3)-N-acetyl-alpha-D-glucosaminyl-diphospho-trans,octa-cis-decaprenol + 28 UDP-alpha-D-galactofuranose = [beta-D-galactofuranosyl-(1->5)-beta-D-galactofuranosyl-(1->6)]14-beta-D-galactofuranosyl-(1->5)-beta-D-galactofuranosyl-(1->4)-alpha-L-rhamnopyranosyl-(1->3)-N-acetyl-alpha-D-glucosaminyl-diphospho-trans,octa-cis-decaprenol + 28 UDP + 28 H(+) — reaction