But if you grant ATC the powers to refuse movement for take off due to the curfew, that shifts part of the decision-making process related to the curfew to them. That decision they are making - whether to give allowance to take off or not - is a legally empowered one according to an Act which is very much not part of the core functions of air traffic control.
The Act needs to include this fact, as well as connect the decision-making process related to dispensations to ATC. It doesn't have to mean ATC are a decision-maker with respect to dispensations, but they are a decision-maker with respect to movement within the curfew.
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