R6800 firmwares have been released. It contains two files.

openwrt-ramips-mt7621-netgear_r6800-squashfs-factory.img: Should be used when you want to upgrade openwrt firmware from Stock firmware

openwrt-ramips-mt7621-netgear_r6800-squashfs-sysupgrade.bin: Should be used when you want to upgrade openwrt firmware from openwrt firmware.

It supports basic features. I would be happy to get your feedback about it and what features you want to see in next version of this firmware.