4. By way of derogation from paragraph 3 of this Article, a hydrogen transmission network operator that benefits from a derogation from Article 68 of Directive (EU) 2024/1788 shall be eligible to become a member of the ENNOH, provided that the operator is established in a Member State where no other hydrogen transmission network operator is a member of the ENNOH pursuant to paragraph 3 of this Article. Member States may nominate such a hydrogen transmission network operator and shall submit any such nomination to the ENNOH, the Commission and ACER. Member States may revoke such a nomination at any time. Where the hydrogen transmission network operator has not taken a final investment decision with regard to a hydrogen infrastructure project within four years of becoming a member of the ENNOH, that operator’s membership of the ENNOH shall expire.