Back in the days of my youth and 1st edition, Imperial Guard could include Beastmen units, they were classified as abhumans. I see that Ratlings and Ogryns have survived, but not so the self loathing Emperor worshiping beast folk. My question is - Is there some narrative mention of Beastmen being turfed out of the guard, ie current lore says Beastmen used to serve in the guard but no longer do.  Or has it been retconned so that there never were any imperial guard Beastmen?