Both the leaks are 100% legit prototypes. As per Steve, we are very early in the production process and the three 2019 iPhones are still in EVT stage (Engineering Validation Test) which means nothing is set in the stone yet. So, we have two cases here,
Case 1: Both the leaked prototypes will be retained and be marketed as two different models (say iPhone XIS and XIS max).
Case 2: One of the leaked prototypes will be axed and the other will be retained.
So could this both designs are 100% legit prototypes? Let wait and watch the upcoming renders on the web.
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