A. In the case of a child who was the subject of a foster care plan filed with the court pursuant to § 16.1-281, a foster care review hearing shall be held within four months of the dispositional hearing at which the foster care plan pursuant to § 16.1-281 was reviewed if the child (i) was placed through an agreement between the parents or guardians and the local board of social services where legal custody remains with the parents or guardians and such agreement has not been dissolved by court order or (ii) is under the legal custody of a local board of social services or a child welfare agency and has not had a petition to terminate parental rights granted, filed or ordered to be filed on the child's behalf; has not been placed in permanent foster care; or is age 16 or over and the plan for the child is not independent living. Any interested party, including the parent, guardian or person who stood in loco parentis prior to the board's placement of the child or the board's or child welfare agency's assumption of legal custody, may file with the court the petition for a foster care review hearing hereinafter described at any time after the initial foster care placement of the child. However, the board or child welfare agency shall file the petition within three months of the dispositional hearing at which the foster care plan was reviewed pursuant to § 16.1-281.