Both are great for portraits, the 85mm focal length is more versatile, IMO. 135mm is good for individual headshots. Your signature indicates you have the 70-200 II, f/2 is close, f/1.2 isn't so close.
While I agree the 85mm FL is more versatile, would you say the 85L as a lens is more versatile than the 135L?
On the other hand, the OP does say the main focus is portraiture- so the 85L is a better lens on an FF camera (from the perspective point of view, pun unintended, in strictly my opinion).
JD, my suggestion to buy the 135L is purely based on the assumption you will get the 85L later. I was merely responding to your original post before you changed it, where you wanted to know which was a better deal.