This subtitle applies only to: guardianship of an individual who is committed to a local department as a child in need of assistance; adoption of an individual who is committed to a local department as a child in need of assistance, without prior termination of parental rights as to the individual; and adoption of an individual under guardianship under this subtitle. This subtitle: does not apply to a guardianship case filed on or before December 31, 2005, until guardianship is granted; and unless otherwise specified, does not apply to an adoption case filed on or before December 31, 2005.