wow the promo is better than the whole last episode in my eyes.
we know that red john is rather old, but still not too old to run away from jane and he jumps through a window. so he has to bit kind of fit.

from the hair we can exclude all people but, mcalister, stiles (maybe cut them short), minelli (how long have we not seen him, maybe he got old in the meantime) and someone everyone has forgotten judge manchester. 

the hair fit all of them, but if we still trust heller with the list, only can be mcalister or stiles. but stiles is too old to run and jump like that.

manchester was not on the list, no one here could have guessed him. minelli was always suspicious but he was not on the list too.

and manchester would be too diffiucult to guess. but i think that manchester is a higher member of the blake association. also that dude from austin texas fbi has a hand in blake.

there is one interesting shot in the internet, where the guy who jumps looks like mcalister, also a pic where you can identify his hand.

but the voice fits manchester better than mcalister or minelli, even though both some how are close. stiles is not even close.

also manchester is really old to be a young man at the barn, he is the age of stiles, if not older.