So, interesting find I have come across. I purchased a Moto Z Play from Amazon - made sure it was the model approved by Republic and it was delivered last week. In getting things set up I noticed that when I pulled the SIM tray out to install my SD card and me SIM - WHOA!!! - there was room for another SIM. I checked the model number on the phone, in the phone OS and on the box and it did INDEED say XT1650-02 (though the international version). Now my wife also has this same version and is has the standard OS image without dual SIMs in the options - it works as well. Both the same model number. Hers came with a US charger while mine was international.
So WTH - i figured I would put in my Tmobile work SIM, as i would love to NOT carry (2) phones all the time.
The phone installed the Republic app and it registered approved and I got it going. The Android OS imaged on the device did infact support (2) SIMs and after a week I can confirm that I can make calls on both republic using towers or wifi and I can make calls on the tmobile sim. IT IS AWESOME!!!
Here is my thought. I wonder if ALL XT1650-02 phones support dual SIM. I think the only difference is that the international version has a slightly different OS with enabled settings and they include a tray that supports two SIMs. I confirmed that the SIM tray fits in both phones. I wonder if I unlocked my wifes phone and flashed the OS from my international version and bought a dual SIM tray on Ebay if it would enable it. I most likely wont to that - but just thinking outloud.
Pretty cool huh!!