iOS 9.3 is coming in the Spring and will introduce Night Shift as well as a number of other new features.
Apple Launches U.S. iPhone Promotion Offering Free Next Day Shipping On All Models
The shipping promotion comes shortly after Apple released a new "Why You'll Love an iPhone" advertising campaign via email and the web and a secondary email advertisement that highlighted Apple’s 9th consecutive J.D. Power Smartphone Satisfaction Rankings win. Apple's advertising push follows the introduction of Samsung's Galaxy S 4 phone.
Potential customers are limited to purchasing two iPhones with the newly released shipping offer, which is available immediately. Though no specific holiday is associated with the promotion, it does come a week before the Easter holiday.