Apparently, GB will be released in the new 4K Blu-ray format when players and titles start rolling out this year.
See here:
http://www.theverge.com/2015/11/11/9713580/4k-uhd-blu-rays-announced-release-date
http://www.engadget.com/2015/11/10/sony-4k-ultra-hd-blu-ray-2016/