TMo will be selling OnePlus 6T with the second SIM disabled as well as bootloader locked. Bootloader can be unlocked after being paid off, but no word on whether the second SIM could even be enabled (might be lack of hardware instead of software). So if you don't have a device to trade in for the $300 credit, just purchase it straight from OnePlus. This ends the public service announcement. While no carriers currently support Apple's eSIM yet, but at least we know it's coming. iPhone XR it is for me. No Dual SIM is not a deal breaker cause I've been using single SIM forever, but when the device in comparison is dual SIM capable, I'll take that!