When it was reported that Kyle Dubas was not going to return to the Leafs, one of the more shocking moments came shortly before the official announcement. That was when Jason Spezza handed in his resignation. It's also been rumoured that Spezza resigned because he did not want to be the interim GM after Dubas was released.
Now, however, Elliotte Friedman has reported that Spezza will be joining Dubas in Pittsburgh. He does not believe it will be as GM, but it will be in some capacity greater than what he was doing with the Leafs.