In this section, “child” means a defendant who is under the age of 18 years and whose case is eligible for transfer under the provisions of § 4-202(b)(1) and (2) and (c) of this subtitle. If a child remains in custody for any reason after a bail review hearing: in the case of a child charged with a felony that is not within the jurisdiction of the District Court, the District Court shall: clearly indicate on the case file and in computer records that the case involves a detained child; and set a preliminary hearing to be held within 15 days after the bail review hearing; or in the case of a child charged with a crime in the District Court, the District Court: shall clearly indicate on the case file and in computer records that the case involves a detained child; shall set a transfer hearing under § 4-202 of this subtitle to be held within 30 days after the filing of the charging document; may order that a study be made under § 4-202 of this subtitle; and shall require that prompt notice be given to counsel for the child, or, if the child is not represented by counsel, to the Office of the Public Defender. On receipt of a District Court case file that indicates that the case involves a child who was detained after a bail review hearing under subsection (b) of this section, a circuit court: unless previously set by the District Court under subsection (b)(2) of this section, shall set a transfer hearing under § 4-202 of this subtitle to be held within 30 days after the filing of the charging document in the circuit court; unless previously ordered by the District Court under subsection (b)(2) of this section, may order that a study be made under § 4-202 of this subtitle; and shall require that prompt notice be given to counsel for the child, or, if the child is not represented by counsel, to the Office of the Public Defender.