X-E1/X-1 Pro with on-chip phase detection AF

I don't think so. I believe the X-Pro1 and X-E1 replacements will be launched at almost the same time, not a year apart.
(Like Nikon does with their V and J series  Same sensor, but flash and OV added for the more expensive model V)

And I will not be surprised if they are announced already at the end of this year along with the announcement of a few more lenses. Especially with all the improvements being added for the X100s.