At its peak in 2012, the Foxconn plant in Zhengzhou had 300,000 factory workers, a number that has since dwindled down to 210,000. The assembly lines usually are revved up at this time of the year in order to accommodate the next version of the iPhone. While one source called the model the Apple iPhone 6, we expect the next model to be called the Apple iPhone 5S with an updated processor, an improved camera and a longer lasting battery.
In China, there is speculation that the plant in Zhengzhou is working on a version of the Apple iPhone with a borderless screen and an aluminum and carbon fiber shell that would make the phone 40% lighter. Since late last year, we have seen leaked pictures alleged to be of the Apple iPhone 5S to pictures of a rumored low-cost version of the Apple iPhone expected for emerging markets. This model would have 8GB of storage, a lower-spec'd camera and processor, and be offered in a variety of colors.
source: Yicai (translated) via AppleInsider