He will be RPSI and American Warmblood. I dont think they have colour biases, but if I register him part APHA they may. I might just go the RPSI and AW though.
After browsing lots of pictures, I agree he looks more smokey brown than buckskin. His baby coat was SOOO light, but I guess that can happen with a smokey brown? Sire looks like a “brown” horse to me…very dark bay.
I think Animal Genetics does coat color testing now, they dont have “smokey brown” as a colour, but could eliminate buckskin or bay I suppose: http://www.horsetesting.com/