Bloomberg reports that Apple has asked Foxconn to take on additional staff at its Zhengzhou factory, where the only Apple product made is the iPhone – suggesting that production may be ramping up for the iPhone 5S and low-cost iPhone launches …

The massive manufacturing facility employes more than a quarter of a million people, with the WSJ citing another un-named source as saying the company has been taking on 10,000 assembly-line workers a week since the end of March. Such data in isolation of course tells us little to nothing about production schedules.

It’s widely-believed that the low-cost iPhone aimed at developing markets will be made available in a range of colors. Rumors about the 5S include a fingerprint sensor, though it would be unusual for Apple to introduce significant hardware changes in an S model.