Though it is not known when Toyoyuki succeeded the family estate, it is assumed he had by around July 1453 when his name appeared as "Yakata Rokuro".
豊之が家督を継いだ時期は不明だが享徳2年（1453年）7月に「屋形六郎」と見えることからこの頃には家督を継いでいたと思われる。