Customers increasingly expect fast and precise delivery information, yet logistics service providers know that committing too early to delivery time windows can seriously undermine route efficiency. A recent paper tackles that tension head-on by asking a deceptively simple question: is it worth waiting before communicating delivery time windows to customers?
The authors focus on next-day services such as high-value deliveries, installations, and B2B services, where providers still control when and how time windows are assigned. Early communication improves customer satisfaction and reduces missed deliveries, but it also locks planners into suboptimal routes when future demand is still unknown. Delaying communication offers planners more flexibility, but risks frustrating customers who are left waiting for confirmation.
To study this trade-off, the paper introduces the Dynamic Delayed Time Window Assignment Vehicle Routing Problem (DDTWAVRP). In this setting, customer requests arrive dynamically over the day before delivery. For each request, the service provider must decide whether to immediately assign a delivery time window or postpone that decision until more information becomes available. Waiting incurs a “customer dissatisfaction cost,” while early assignment can increase routing costs and time-window violations the next day.
Methodologically, the authors model the problem as a sequential decision process and test two practical online decision policies. The first is a rollout policy that uses short-term look-ahead simulations to balance customer wait time with expected routing efficiency. The second is a multiple-scenario approach that focuses on finding time windows that remain feasible across many possible future demand scenarios. These approaches are compared with simpler strategies, such as assigning all time windows immediately, postponing everything until the end of the day, or assigning time windows at fixed cut-off moments.
The results are highly relevant for real-world operations. The numerical experiments show that selectively delaying time window assignments can significantly improve routing performance. Using the rollout policy, routing durations decrease by nearly 12% compared with immediate assignment, while most customers wait less than an hour for their time window. Significantly, routing costs increase only marginally compared with the extreme strategy of postponing all assignments until the very end. This suggests that thoughtful, selective waiting captures most of the planning benefits without seriously harming service levels.
Another important insight is that waiting should not be applied uniformly. The optimal decision depends on the system’s state, including current demand patterns and remaining planning time. Some customers are best served with immediate confirmation, while others benefit from delayed assignment. The study also finds no substantial evidence that selective waiting systematically disadvantages specific customers, for example, those further from the depot, at least under the rollout policy.
For logistics professionals, the message is clear. The timing of customer communication is not just a service issue but a powerful planning lever. Rather than choosing between “always early” or “always late,” operators can use data-driven, dynamic policies to decide when commitment makes sense. As customer expectations rise and routing problems become more complex, actively managing when promises are made may become just as important as how routes are planned.