2016-17 sounds about right for when perhaps he might fancy trying his hand at one of the two Spanish teams, he would be around 29 by then, and from our POV it is debatable if a player can keep up his current level of stamina past that sort of age. Most at least slow down or adjust their style, especially in the modern game.
His future is also tied to ours, even ignoring what happens at other clubs. Just great to have him here.
Not trying to jump the gun or tempt fate, but looking ahead it's a strong possibility.