Two ECJ rulings first.
Stand-by time and working time. In a ruling Case C-518/15 (Matzak), handed down on 21 February by the Court of Justice of the European Union, judges clarified that stand-by time which a worker (in this case a firefighter) is required to spend at home with the duty to respond to calls from his employer within eight minutes – which very significantly restricts the opportunities to carry out other activities – must be regarded as ‘working time’.
For the CJEU, when a worker is on stand-by duty and is available within constraints that mean the worker is constantly contactable, but without actually having to remain physically present at work, and can devote himself/herself to personal and social interests, then only the time spent providing services should be considered as ‘working time’.