A report last week stated that the design of the new Apple chip, the A9 and it's sibling the A9X, has been almost finalized, and will begin pre-production soon. Which will not come as a surprise and it's almost a dead certainty that the next iPhone will be announced and released in September 2015.
The report stated:
We believe TSMC will earn most of the A9 orders thanks to its superior yield ramp and manufacturing excellence in mass-production. We expect TSMC to earn all of Apple’s A9X orders (for the next generation iPad) and most of the A9 (for the next generation of iPhone), aggregating to an allocation of over 70%.(source Barrons Asia)