You understand that maybe the club c/should have given him a better heads-up on this, but he's the one who made the whole thing a lot worse by yapping to the press about how pissed off he was over it. What he wants (and has apparently asked about in the past) is for the Mets to pick up the option they have on him for 2018. Players like to look for any leverage they might have (like by waiving a No-Trade clause) to pressure clubs into more guaranteed money and it sounds like he saw this as an opportunity to make a deal: I'll agree to the switch if you agree to the option. Problem is that, between his injuries, his season, his advancing age, and Rosario in his mirror, he's not exactly in a strong bargaining position and then started pouting when his ploy didn't work. In the end I don't know that he was ever more than a 50/50 bet to picked up anyway and he wasn't going to be the 2018 SS even if he did, all of which makes his protests seem out of proportion to forced move. And while sitting him now out of spite or as a version of punishment for yapping doesn't really do anyone any good, the fact that neither he nor the team is having the year they envisioned means that the time he was likely to become an ex-NYM had already jumped up from October to July and last night's soap opera will be largely irrelevant as to either the reason or the timing in that.