Amazon Prime subscribers in India will be able to purchase the OnePlus 3T before everyone else

If you're a subscriber to Amazon Prime over in India, you can now register to be eligible to purchase the latest OnePlus smartphone on December 12th - two days before everyone else. You'll need to register on Amazon's site before 2:00 PM on December 12, but being eligible doesn't mean that you're guaranteed to get the phone. Available quantities of the phone are expected to be limited, so you'll want to register sooner rather than later to ensure that you don't miss out on this deal. And, if you aren't currently a subscriber to Amazon Prime, you can sign up for a free trial of the service and register for the early sale just like normal subscribers to Amazon's premium service.
source: Amazon via Android Authority