According to Canonrumors, the rumored Canon EOS 6D Mark II will be announced in February, 2017. Release date set in March/April, 2017.
As the Canon EOS 5D Mark IV is set to announced in late August, 2016, there wont be enough time to launch an EOS 6D Mark II in 2016. The only other camera coming in 2016 will be a new mirrorless camera, probably a new full frame mirrorless camera from Canon.
According to rumors, the Canon EOS 6D Mark II will have a new 24MP full frame sensor which would be used on upcoming Canon EOS 5D Mark IV.
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