5. By way of derogation from paragraph 4 of this Article, if a Member State considers that it is not possible to put in place restoration measures by 2050 that are necessary to reach the favourable reference area for a specific habitat type on 100 % of the surface, the Member State concerned may set a lower percentage at a level between 90 % and 100 % in its national restoration plan as referred to in Article 15 and provide adequate justification. In such a case, the Member State shall gradually put in place restoration measures that are necessary to achieve that lower percentage by 2050. By 2030, those restoration measures shall cover at least 30 % of the additional surface needed to achieve such lower percentage by 2050, and by 2040, they shall cover at least 60 % of the additional surface needed to achieve such lower percentage by 2050.