Judgment of the Court (Grand Chamber) of 15 April 2021.#H. A. v État belge.#Request for a preliminary ruling from the Conseil d'État.#Reference for a preliminary ruling – Regulation (EU) No 604/2013 – Determination of the Member State responsible for examining an application for international protection – Article 27 – Remedy – Whether account should be taken of circumstances subsequent to the transfer decision – Effective judicial protection.#Case C-194/19.