Yahoo appears to set their position assignments fairly early. Apparently before much information is available about how they will actually be used by the team drafting them. Their policy is once they set a position assignment, they will add a new one if the old one is wrong, but they will not take one away during the season in case players made assumptions based on that original assignment.They do this every year with a few players. Last year they originally thought Chris Cooley would be an H-back/FB so they put him as RB, then added TE. Colston was listed as a TE by the NFL during the draft so he's now TE,WR. Robinson was listed as a WR during the draft so he's now a WR,RB.