1) According to Article 412 (5) of Regulation (EU) No 575/2013, Member States may maintain or introduce national provisions in the area of liquidity requirements until binding minimum standards for liquidity coverage requirements are fully introduced in the Union in accordance with Article 460, which means until 1 January 2018 (or until 1 January 2019 in case the Commission decides to alter the phase-in specified in Article 460 and defer until 2019 the introduction of a 100 % binding minimum standard for the liquidity coverage requirement). Doing so, they shall not circumvent the introduction of the liquidity coverage requirement from 2015 onwards as described in Article 460 of Regulation (EU) No 575/2013.
2) The second sentence of Article 412 (5) of Regulation (EU) No 575/2013 does not relate to national liquidity requirements but instead to the liquidity coverage requirement as detailed in the delegated act mentioned in Article 460. Under this provision, Member States may implement this requirement at a higher speed than specified in Article 460 (2).
This question goes beyond matters of consistent and effective application of the regulatory framework. A Directorate–General of the Commission (Directorate General for Internal Market and Services) has prepared the answer, albeit that only the Court of Justice of the European Union can provide definitive interpretations of EU legislation. This is an unofficial opinion of that Directorate General, which the European Banking Authority publishes on its behalf. The answers are not binding on the European Commission as an institution. You should be aware that the European Commission could adopt a position different from the one expressed in such Q&As, for instance in infringement proceedings or after a detailed examination of a specific case or on the basis of any new legal or factual elements that may have been brought to its attention.