He can't say he's leaving because there is no job to leave for at this time. He is either still deciding (hopefully), or he's made his decision to leave and is just waiting for the job to officially open.
That's not necessarily true. The Bulls job isn't open, but the Magic, Pelicans, and Timberwolves* jobs are. Fred can definitely say that he will be coaching in the NBA next year, but where is still yet to be determined.