It has been confirmed that on September 8th that 2K plans on releasing the prelude for NBA 2K18. The prelude consist of players previewing and demoing NBA 2K18 by playing through the college years of your MyCareer before getting drafted.
Just like last year, the prelude is confirmed for the PS4 and Xbox One only. The full game is set to release on September 19th, with four days early access on September 15th. The full game is releasing on the PS4, Xbox One, PC, and the Nintendo Switch.