Sadly, I think our last, best hopes for revisiting Red John, at least anytime soon has gone with the title of 6x13 being revealed to be 'Black Helicopters'.

I was holding out hope that the withholding of the title of the episode was meaningful and would come with 'Red' as the colour within it...I fear we may indeed be stuck with 6x8 as the close to the arc...sad days.