Answer was provided by the European Commission 

Where two or more authorities exercise the same role as referred to in Article 4(2) CCPRRR in relation to the same entity, such authorities are to be considered as a single member of the resolution college. Accordingly, they will express only one vote and would need to agree amongst themselves on the vote to cast.
Any interpretation provided in this Q&A is strictly limited to the CCPRRR and should not be construed as providing any guidance on or limitation to the application of any other EU legislation.

Disclaimer 

The answers clarify provisions already contained in the applicable legislation. They do not extend in any way the rights and obligations deriving from such legislation nor do they introduce any additional requirements for the concerned operators and competent authorities. The answers are merely intended to assist natural or legal persons, including competent authorities and Union institutions and bodies in clarifying the application or implementation of the relevant legal provisions. Only the Court of Justice of the European Union is competent to authoritatively interpret Union law. The views expressed in the internal Commission Decision cannot prejudge the position that the European Commission might take before the Union and national courts.