Nested ticketing represents a prevalent practice in airline bookings, employed to bypass certain airline ticketing regulations with the aim of reducing costs on multiple round-trip tickets. We consider the computational complexity of nested ticketing, and it is ‘covert’ version, which we call interleaved ticketing. Consider multiple agents living in different locations and a single client who demands that one agent be present each week. The objective for the company is to schedule these agents and arrange their flight itineraries to minimize the cost. We show that when nested ticketing is allowed, the problem is NP-hard when there are at least two agents. We also show there exists a polynomial-time algorithm if only interleaved ticketing is allowed, and the number of airlines is bounded.