We were expecting Xiaomi to launch a second device other than the Mi Mix 2 at the September 11 launch event.
Even though some rumors claimed the second device to be launched as the Mi 6 Plus, we can now confirm that the second device that will launch on September 11 will be the Mi Note 3.
The co-founder of Xiaomi, Lin Bin, on Weibo has come up with a teaser image of the Xiaomi Mi Note 3 with a caption that says if users wanted the Mix Mix 2 or a larger Mi 6.
As the caption accompanies the Mi Note 3 teaser image, it is safe to assume that the larger Mi 6 he refers to, is the Mi Note 3 and that we can see the Mi Note 3 launch on September 11.
I think in the three different pictures represent three different phone colors.