User blog comment:B214/Light Novel Volume 16 spoilers/@comment-6096197-20131020081334/@comment-16281343-20131020110733

Maybe just a functionality upgrade? Like Siegfried's Twice Critical's BB where he just doubles the number of his arms?

In Valerie's BB.. she just increases the number of Sephiroth Grall to three so that others other than her can use the SG.