The fish in the photo to me, looks like a color phase of a pure strain BG. Note the lack of a color margin of the gill flap. Unless I am missing something the gill flap appears to be all black to the back margin. Some sort of colored or light color margin is present on almost all HBG. The fins also do not show any color pattern different than those of a 'regular' BG.
The only things I questioned on the fish being pure BG Bill is the mouth looks big for a pure BG (could be it just looks that way because it is stretched open though) and the pectoral fin looks pretty short rather than intermediate length. Maybe just the way it is fanned out but looks more like a GSF type pectoral fin.
Edit: I see the line coming out of the mouth now so maybe just the way the bait is swallowed is making the mouth look big.
