iOS 9.3 is coming in the Spring and will introduce Night Shift as well as a number of other new features.
Shipments of New iPhone Models Begin Arriving in the U.S. Ahead of Next Week's Media Event
As is not unheard of for the company, Apple is already beginning to stockpile units in the United States for quick distribution to carrier partners, other third-party retail partners, and its own channels. With the new iPhone hardware expected to be introduced at next Tuesday's media event, Apple's pattern with previous releases suggests that the new models would launch in the U.S. and other first wave countries about a week and a half later, with Friday, September 20 being the most likely date.
C Technology, which has been posting a number of photos of alleged iPhone 5C units, packaging, and manuals, has also claimed on its Sina Weibo account (via @MobilesPie) that 1.2 million iPhone 5C units were shipped to the United States yesterday.
With the packaged iPhone 5C units showing up in a number of photographs over the past few days, it seems reasonable to believe that the device may indeed be ready for shipment ahead of next week's media event. Little to no specific evidence of iPhone 5S units being ready for shipment has been seen, and it is unclear whether that device is included in the U.S. shipments we are hearing about.