I was under the illusion that the R3P back end ROM was was very similar if not pretty much the same as OpenWRT. I really hope it gets supported as I've bought one now. Its just being used as an access point at the moment as I use pfsense as my primary router at home for the most part.
I guess I could be a tester for one of the devs with my 24hr old router (gulp)
It's such a nice well built bit of kit, it would be a shame to see it left idle on this heavily restricted official Xiaomi ROM.