I say a topic on this, mine is a 512 gb silver 512 gb factory unlocked still on iOS 12.0 and I use t mobile and I'm running two Sims perfectly one is t mobile but......one is telcel Mexico and both work fine. Not sure if this is a two t mobile numbers or two different USA networks that iOS 12.1 is going to work on???? Maybe the factory unlocked version works now but not the network locked?? But mines running two numbers now as I type this on my iPhone xs max..
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