Where a specific methodology for demonstrating compliance is prescribed in the regulation, does this specific provision override a general one ?

Yes, where a specific methodology is prescribed in the implementing measure, it overrides a general one.

Unless explicitly stated otherwise, the provisions contained in the measurement and calculation Annex of the Regulations are of a mandatory nature. They override equivalent provisions in relevant standards and methods.

_{Disclaimer: Please note that the European Commission cannot provide a legally binding interpretation of the EU legislation, as this is the sole competence of the European Court of Justice. Any remarks from the European Commission services are without prejudice to the position the Commission might take should related cases arise in a procedure before the Court of Justice.}