Developers Steve Troughton-Smith and Christopher Anderson found references to the names when going through the firmware:
…and we now have the name of all three new iPhones. Are you ready for this?
iPhone 8 Plus
Apple is set to unveil the new iPhones on September 12th. There had been some recent speculation that the names would be iPhone 8, iPhone 8 Plus, and iPhone Edition; however, the iPhone X name now seems much more likely.
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