Firmware Version 1.0.3:

Corrects an erroneous display that may appear when some third-party accessories are attached to the hot shoe.

https://www.usa.canon.com/internet/portal/us/home/support/details/cameras/dslr/eos-6d-mark-ii?subtab=downloads-firmware

Review

Canon still does not offer 4K video in many of its cameras, including the new 6D II. While we don't fully understand the decision, it is what it is. Fortunately, Full HD video quality is pretty good on the 6D Mark II. Further, the 6D II is the first full-frame EOS camera to include 5-axis in-camera digital stabilization, which does work quite nicely, although it crops the video and does decrease the image quality slightly.

1080p video is not very sharp still, but it looks pretty good across a wide range of ISO speeds, which makes the 6D II a pretty versatile video camera. Even at ISO 6400, we still found the video usable. Automatic exposure and autofocus performance was good too, particularly the autofocus. Dual Pixel CMOS AF certainly helps a lot here.

Lack of 4K video recording is a big knock on the 6D II, but for users who only need 1920 x 1080 video, the 6D II should prove to be a fine option, although it is certainly not a videographer's camera.

http://www.imaging-resource.com/PRODS/canon-6d-mark-ii/canon-6d-mark-iiA7.HTM

New Meike battery grip

Grip uses pair of LP-E6 / LP-E6N batteries. It allows easier vertical shooting and can double the usage time of the camera. There is a built-in 2.4g wireless remote function which can be triggered up to 100m away.

Allows you to shoot long exposure and interval shots via the remote.

Pricing and availability are unknown for now.

EOS 6D Mark II Body Refurbished, $1499

https://shop.usa.canon.com/shop/en/catalog/eos-6d-mark-ii-body-refurbished

Video not too good

https://www.imaging-resource.com/PRODS/canon-6d-mark-ii/canon-6d-mark-iiVIDEO.HTM

EOS 6D Mark II Body Refurbished, $880

https://shop.usa.canon.com/shop/en/catalog/eos-6d-mark-ii-body-refurbished