Case C-563/17: Judgment of the Court of Justice (Second Chamber) of 27 February 2019 (request for a preliminary ruling from the Supremo Tribunal Administrativo — Portugal) — Associação Peço a Palavra and Others v Conselho de Ministros (Reference for a preliminary ruling — Freedom of establishment — Regulation (EC) No 1008/2008 — Air carrier company — Reprivatisation process — Sale of shares representing up to 61 % of the share capital — Conditions — Requirement to keep the headquarters and effective management in a Member State — Public service obligations — Requirement to maintain and develop the existing national hub)