There's apparently going to be a staggered release for the Nintendo Switch version of NBA 2K18. The details on the release are a little bit sketchy, but apparently 2K Games doesn't quite have as much faith in the Switch release of the game that Nintendo has in their own games.
Game Informer is reporting that in Take-Two Interactive's financials, there's a mention that the digital version of NBA 2K18 for the Nintendo Switch will have launch parity with the Xbox One, PS4, PS3 and Xbox 360 versions of the basketball title next month on September 19th.
The major difference is that in addition to all of those systems having digital releases, they will also have physical releases of NBA 2K18 as well. The Nintendo Switch version's physical release is apparently scheduled to launch at some point in the "Fall" of 2017. So there will be a staggered physical release of the Switch's version.
There is no actual reason given by Take-Two, who is the parent company over 2K Games and 2K Sports, as to why there is a delay for the physical version of NBA 2K18 on the Switch, but some speculate that it may have to do with the size of the game fitting on the Switch's standard cart.
The cart size apparently goes up to a standard 32GB, which is less than half the size of NBA 2K17, which requires about 70GB of space. NBA 2K17 on PS4 and Xbox One before patches was just under 50GB. So even still the cart's size is way off from where it should be to contain a game like NBA 2K. Also keep in mind that it's unlikely that NBA 2K18 would be any smaller than NBA 2K17, so this would mean that 2K Sports would have to make a few key decisions when it comes to the physical packaging for the game.
The developers could either purchase higher capacity SD carts to store the game on, which is something that some studios would do for large-scale N64 games back in the day like Perfect Dark, WWF No Mercy or The Legend of Zelda: Ocarina of Time. However, there are questions as to whether or not 2K Sports and Take-Two feel as if the Switch version of NBA 2K18 would be worth the cost to invest in a larger cart.
There's also the possibility of storing the game on two separate carts; one cart for the single-player and one for the multiplayer. This was something that Microsoft had begun doing for Xbox 360 games, including titles like Halo 3: ODST and Halo: Reach. Games like Lost Odyssey, L.A. Noire and Mass Effect also came on multiple discs for the Xbox 360 due to the limited DVD9 storage capacity. Multiple discs were usually a last resort, though, since high-compression or hard-drive installation storage was always the preferred method, when applicable.
In the case of the Nintendo Switch, though, most games have either been a full cart release or a full digital release. There hasn't been a game yet that spans multiple carts or requires both cart and hard drive installation, since the logistics could create a rather confusing and disruptive user experience.
Some people think that Take-Two and 2K will monitor the digital sales for NBA 2K18 first on the Nintendo Switch and if things go over well then a physical release will be made available for Nintendo's console.