Xperia Z3v Simultaneous LTE and Voice Service

I'm told by Verizon that the Z3v will be unable to access mobile data while in a call until January. If only they told you this *before* the sale! In any case, does anyone know of a workaround, or a way to get the software update early? I considered flashing something from Sony's developer world, but as I understand it this will impact camera functionality... Any known way to get around this without waiting until Sony/Verizon push the update? "Mobile data not available" (click image for larger variant)