Judgment of the Court (Eighth Chamber) of 9 July 2020.#'Unipack' АD v Direktor na Teritorialna direktsia ‘Dunavska’ of the Agentsia ‘Mitnitsi’ and Prokuror ot Varhovna administrativna prokuratura na Republika Bulgaria.#Request for a preliminary ruling from the Varhoven administrativen sad.#Reference for a preliminary ruling – Customs union – Union Customs Code – Delegated Regulation (EU) 2015/2446 – Article 172(2) – Authorisation to use the end-use procedure – Retroactive effect – Concept of ‘exceptional circumstances’ – Amendment of the tariff classification – Expiry of validity of a decision relating to binding tariff information.#Case C-391/19.