As of this afternoon, the museum’s timed passes are entirely sold out for the rest of the year. If you want to reserve time to make the trip, you’ll have to wait until the museum starts giving out passes for January.
BUT. That doesn’t mean it’s impossible to visit before 2017 if you don’t already have a ticket. After this weekend, the museum will start releasing same-day passes each morning on a first-come, first-served basis.
Starting on Monday, September 26, the museum will start handing out free, timed same-day passes at 9:15 AM. The museum has more information available on that, here.