A report from Bloomberg appears to confirm rumors that two larger new iPhones are on the way and may be available in September.

Apple suppliers will begin production of the new phones in China next month, Bloomberg’s Tim Culpan and Peter Burrows reported, citing unnamed sources familiar with the plans.

Both phones boast larger screens than the four-inch display of the iPhone 5S. One model with a 4.7-inch screen is expected to ship to retailers around September, when Apply typically releases its new phones, according to two people Bloomberg spoke with. A 5.5-inch version may be available at the same time, the sources said. But the bigger model has proven harder to produce, so its arrival could be delayed by slower production.

MacRumors had previously reported that issues with battery life and display technology in the larger phone could result in a release several months after the 4.7-inch model. Earlier this month, MacRumors reported the Chinese Web site Laoyaoba claimed Apple had solved its battery issues, though it wasn’t clear whether both new phones would launch at the same time.

Screen size has become a more important consideration for many smartphone users who now spend more time on mobile devices than desktop computers. Most Android phones, including the popular new Samsung Galaxy S5, which has a 5.1 inch screen, have a larger screen than the iPhone.

The new iPhones will be rounder and thinner than their older siblings. Bloomberg had previously reported the new screens will feature curved glass and enhanced sensors that detect changing blood pressure levels – a feature presumably designed to work with Apple’s new HealthKit app.

In March, analysts with International Strategy & Investment Group said the screen size upgrades will trigger “the ‘mother lode’ of all Apple upgrade cycles” due to pent-up customer demand, according to an investor’s note obtained by Business Insider.