What I find most ominous is the timing -- just a week after the release of v11 with Jack's added PBP.  Sounds suspiciously like he was kept on just long enough to make sure there weren't bugs with the newly released PBP.  On the other hand, if the separation was Jack's choice, perhaps he wanted to stay on long enough to see v11 through to its release, but if I had to guess that is the much less likely scenarios.