According to DigiTimes Research, Apple’s 2017 smartphone line-up with include a 5.8-inch iPhone with a glass casing reinforced by a stainless steel frame and a 4.7-inch iPhone with an aluminum frame.
The design for a 5.5-inch model's chassis has yet to be confirmed, the article says. The reinforced glass chassis' stainless steel metal frame will be supplied by Foxconn Technology and US-based Jabil Circuit, while the aluminum-alloy chassis will be supplied by Catcher Technology, according to DigiTimes. Since the 5.8-inch model is expected to adopt an OLED panel, the smartphone's price is estimated at more than $1,000, the report says.
Chances this rumor is true (IMHO): 90%. Heck, there are so many rumors about the “iPhone 8” that some of them will materialize and others won’t.