a provision in a collective agreement which provides for a longer period for incremental advancement for employment at the start of a career, thereby making it more difficult to advance to the next salary step, constitutes an indirect difference in treatment based on age,
and, if such is the case, that such a rule is appropriate and necessary in the light of the limited professional experience at the start of a career?
Is Article 21 of the Charter of Fundamental Rights of the European Union, in conjunction with Article 2(1) and (2) and Article 6 of Council Directive 2000/78/EC, 1 and also having regard to Article 28 of the Charter of Fundamental Rights, to be interpreted as meaning that