“…This can be formulated as a search over permutations, the well-known Travelling Salesman Problem, an instance of which exists for each collection trip. Furthermore, the order in which routes are allocated to vehicles has been shown to make a small, but nevertheless notable, difference to total transit times for QPPTW [4,17]. Simply, because the routes are reserved via the time-windows, it is possible for an earlier truck to be routed in such a way that it prevents several later trucks being routed optimally.…”