Case C-313/22, ACHILLEION: Judgment of the Court (Eighth Chamber) of 13 July 2023 (request for a preliminary ruling from the Elegktiko Synedrio — Greece) — Achilleion Anomymi Xenodocheiaki Etaireia v Elliniko Dimosio (Reference for a preliminary ruling — Structural Funds — European Regional Development Fund (ERDF) — Co-financing — Regulation (EC) No 1260/1999 — Articles 30(4) and 39(1) — Durability of investment operations — ‘Substantial modification’ of a co-financed investment operation — Recovery of aid in the event of transfer of the establishment which is the subject of that operation — Effect of the specific circumstances surrounding that transfer)