{"id":127992,"date":"2026-05-28T15:24:37","date_gmt":"2026-05-28T14:24:37","guid":{"rendered":"https:\/\/antsroute.com\/?p=127992"},"modified":"2026-05-28T15:36:57","modified_gmt":"2026-05-28T14:36:57","slug":"vrptw-time-windows","status":"publish","type":"post","link":"https:\/\/antsroute.com\/en\/solutions\/vrptw-time-windows\/","title":{"rendered":"Why time windows make route optimisation much more difficult"},"content":{"rendered":"<div class=\"wpb-content-wrapper\">[vc_row css=&#8221;.vc_custom_1735829915094{margin-top: 50px !important;}&#8221;][vc_column width=&#8221;1\/12&#8243; el_class=&#8221;vc_hidden-xs Extra Small Screen vc_hidden-sm Small Screen&#8221;][\/vc_column][vc_column width=&#8221;10\/12&#8243;][vc_row_inner el_class=&#8221;vc_row-2&#8243;][vc_column_inner el_class=&#8221;vc_hidden-xs Extra Small Screen vc_hidden-sm Small Screen&#8221; width=&#8221;1\/12&#8243;][\/vc_column_inner][vc_column_inner width=&#8221;10\/12&#8243;][vc_column_text css=&#8221;.vc_custom_1779977489629{margin-top: 5px !important;}&#8221;]<a style=\"text-decoration: none; color: #1a1a1a; font-size: 18px; font-weight: 500;\" href=\"https:\/\/antsroute.com\/en\/blog\/\">Blog<\/a> &gt; <span style=\"color: #5d75e7; font-size: 18px; font-weight: 500;\">Route optimisation<\/span> &gt; <span style=\"color: #a7a7a7; font-size: 18px;\">Why time windows make route optimisation much more difficult<\/span>[\/vc_column_text][vc_column_text css=&#8221;&#8221;]\n<h1>Why time windows make route optimisation much more difficult<\/h1>\n[\/vc_column_text][vc_column_text]\n<p class=\"text-head\" style=\"color: #424762; font-size: 16px;\">Published on <span style=\"font-weight: 500;\">28 May 2026<\/span> <span class=\"span-reading-time rt-reading-time\"><span class=\"rt-label rt-prefix\"> \u2022 Reading time: <\/span> <span class=\"rt-time\"> 6<\/span> <span class=\"rt-label rt-postfix\">min read<\/span><\/span>\n[\/vc_column_text][vc_column_text css=&#8221;&#8221;]<img decoding=\"async\" class=\"aligncenter wp-image-127994\" style=\"border-radius: 5px;\" src=\"https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-1.webp\" alt=\"AntsRoute banner featuring the headline \u201cWhy time windows make route optimisation much more difficult.\u201d. On the right, a route map displays multiple stops with time slots, delay alerts, and reduced time buffers. Beneath the headline, four icons illustrate delay propagation, waiting times, the loss of time buffers, and time window saturation.\" width=\"1600\" height=\"847\" srcset=\"https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-1.webp 1629w, https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-1-300x159.webp 300w, https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-1-1024x542.webp 1024w, https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-1-768x406.webp 768w, https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-1-1536x813.webp 1536w, https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-1-142x75.webp 142w, https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-1-700x370.webp 700w\" sizes=\"(max-width:767px) 700px, (max-width:1600px) 100vw, 1600px\" \/>[\/vc_column_text][\/vc_column_inner][vc_column_inner el_class=&#8221;vc_hidden-xs Extra Small Screen vc_hidden-sm Small Screen&#8221; width=&#8221;1\/12&#8243;][\/vc_column_inner][\/vc_row_inner][vc_row_inner el_class=&#8221;vc_row-2&#8243;][vc_column_inner el_class=&#8221;vc_hidden-xs Extra Small Screen vc_hidden-sm Small Screen&#8221; width=&#8221;2\/12&#8243;][\/vc_column_inner][vc_column_inner width=&#8221;8\/12&#8243;][vc_column_text css=&#8221;&#8221;]In a classic routing problem, optimising a route essentially means organising a sequence of journeys while minimising the distances travelled.<\/p>\n<p>The introduction of time windows completely changes the nature of the problem.<\/p>\n<p>As soon as each task must be completed within a specific time interval, the route is no longer just a geographical structure. It also becomes a highly constrained temporal structure. And this time-related dimension creates particularly complex effects:<\/p>\n<ul id=\"imglist\">\n<li>delay propagation,<\/li>\n<li>reduced flexibility,<\/li>\n<li>saturation of certain time slots,<\/li>\n<li>increased waiting times,<\/li>\n<li>and the gradual destabilisation of routes.<\/li>\n<\/ul>\n<p>This is precisely what makes VRPTW (Vehicle Routing Problem with Time Windows) problems far more difficult to solve than traditional routing problems.<\/p>\n<p>This article deliberately focuses on the impact of time constraints within route optimisation engines. For a broader overview of last-mile logistics challenges, you can also read our <strong><a href=\"https:\/\/antsroute.com\/en\/solutions\/route-optimisation-complexity\/\"><u>comprehensive article on route optimisation<\/u><\/a><\/strong>.<\/p>\n<p>At AntsRoute, this issue plays a central role in the design of the optimisation engine.<\/p>\n<p><strong>What\u2019s covered in this article<\/strong>:<\/p>\n<ul id=\"imglist-3\">\n<li><a href=\"#a-vrptw-route-is-no-longer-just-a-distance-problem\"><u>VRPTW: much more than a distance problem<\/u><\/a><\/li>\n<li><a href=\"#time-propagation-completely-changes-the-nature-of-the-problem\"><u>Why time propagation makes route planning more complex<\/u><\/a><\/li>\n<li><a href=\"#waiting-times-significantly-reduce-route-efficiency\"><u>The impact of waiting times on optimisation<\/u><\/a><\/li>\n<li><a href=\"#not-all-time-windows-have-the-same-impact\"><u>Time windows with very different operational effects<\/u><\/a><\/li>\n<li><a href=\"#filtering-candidate-time-slots-becomes-essential\"><u>Why time slot filtering is essential<\/u><\/a><\/li>\n<li><a href=\"#time-buffers-become-a-strategic-resource\"><u>Time buffers as a strategic resource<\/u><\/a><\/li>\n<li><a href=\"#time-windows-amplify-the-side-effects-of-insertions\"><u>The side effects of dynamic insertions<\/u><\/a><\/li>\n<li><a href=\"#why-exact-methods-quickly-reach-their-limits\"><u>Why exact methods eventually reach their limits<\/u><\/a><\/li>\n<\/ul>\n<h2 id=\"a-vrptw-route-is-no-longer-just-a-distance-problem\"><span id=\"A_VRPTW_route_is_no_longer_just_a_distance_problem\">A VRPTW route is no longer just a distance problem<\/span><\/h2>\n<p>In a traditional VRP, two geographically similar solutions will generally behave in fairly similar ways.<\/p>\n<p>In a <strong>VRPTW<\/strong>, that is no longer the case. Two routes that are almost identical spatially can exhibit completely different temporal behaviours depending on:<\/p>\n<ul id=\"imglist\">\n<li>customer time windows,<\/li>\n<li>service durations,<\/li>\n<li>waiting times,<\/li>\n<li>or the distribution of time buffers.<\/li>\n<\/ul>\n<p>As <a href=\"https:\/\/www.linkedin.com\/in\/ammar-oulamara-5b837177\" target=\"_blank\" rel=\"noopener\"><u>Ammar Oulamara<\/u><\/a>, R&amp;D Manager at AntsRoute, explains:<\/p>\n<p>\u201cAs soon as time windows come into play, the problem stops being purely geographical. Every insertion changes a chain of temporal dependencies across the entire route.\u201d<\/p>\n<p>This <strong>propagation of constraints<\/strong> is one of the main challenges faced by dynamic routing systems.<\/p>\n<h2 id=\"time-propagation-completely-changes-the-nature-of-the-problem\"><span id=\"Time_propagation_completely_changes_the_nature_of_the_problem\">Time propagation completely changes the nature of the problem<\/span><\/h2>\n<p>In a VRPTW, every arrival time implicitly depends on:<\/p>\n<ul id=\"imglist\">\n<li>previous travel times,<\/li>\n<li>service durations,<\/li>\n<li>accumulated waiting times,<\/li>\n<li>and the delays generated earlier in the route.<\/li>\n<\/ul>\n<p>When a new task is inserted, the optimisation engine must dynamically recalculate the entire temporal structure of the schedule: arrival times, waiting times, potential delays, remaining buffers, as well as the feasibility of subsequent jobs.<\/p>\n<p>This propagation creates significant side effects. A delay of just a few minutes in the middle of a route can, for example, shift a mandatory break, eliminate several time buffers, or even trigger violations several stops later.<\/p>\n<p>In highly dense routes, these effects become particularly difficult to absorb.<\/p>\n<p><a href=\"https:\/\/calendly.com\/lea-brice-antsroute\/demonstration\" target=\"_blank\" rel=\"noopener\"><img decoding=\"async\" class=\"aligncenter wp-image-126567 size-full\" style=\"border-radius: 5px;\" src=\"https:\/\/antsroute.com\/wp-content\/uploads\/antsroute-cta-book-demo.webp\" alt=\"Call-to-action banner for AntsRoute featuring route optimisation software, a delivery route map interface, and a \u201cBook a demo\u201d button highlighting reduced mileage and improved customer satisfaction.\" width=\"1600\" height=\"499\" srcset=\"https:\/\/antsroute.com\/wp-content\/uploads\/antsroute-cta-book-demo.webp 1600w, https:\/\/antsroute.com\/wp-content\/uploads\/antsroute-cta-book-demo-300x94.webp 300w, https:\/\/antsroute.com\/wp-content\/uploads\/antsroute-cta-book-demo-1024x319.webp 1024w, https:\/\/antsroute.com\/wp-content\/uploads\/antsroute-cta-book-demo-768x240.webp 768w, https:\/\/antsroute.com\/wp-content\/uploads\/antsroute-cta-book-demo-1536x479.webp 1536w, https:\/\/antsroute.com\/wp-content\/uploads\/antsroute-cta-book-demo-150x47.webp 150w, https:\/\/antsroute.com\/wp-content\/uploads\/antsroute-cta-book-demo-700x218.webp 700w\" sizes=\"(max-width:767px) 700px, (max-width:1600px) 100vw, 1600px\" \/><\/a><\/p>\n<h2 id=\"waiting-times-significantly-reduce-route-efficiency\"><span id=\"Waiting_times_significantly_reduce_route_efficiency\">Waiting times significantly reduce route efficiency<\/span><\/h2>\n<p>Time windows do not only create delays. They also generate waiting periods when a vehicle arrives before the start of a customer\u2019s time window and must remain idle until the job can begin. In a VRPTW model, this idle time gradually reduces driver productivity, route density, the ability to absorb disruptions, and the overall quality of the schedule.<\/p>\n<p>At AntsRoute, the optimisation engine explicitly penalises these waiting times:<br \/>\n<strong>min \u03a3\u1d62 max(0, e\u1d62 \u2212 t\u1d62)<\/strong><\/p>\n<p>where:<\/p>\n<ul id=\"imglist\">\n<li>ei represents the opening time of the customer\u2019s time window;<\/li>\n<li>and ti the estimated arrival time.<\/li>\n<\/ul>\n<p>As Ammar Oulamara points out:<\/p>\n<p class=\"summary-block\">\u201cA route can be perfectly feasible while still being operationally poor because of the idle time it creates.\u201d<\/p>\n<p>This distinction is essential.<\/p>\n<h2 id=\"not-all-time-windows-have-the-same-impact\"><span id=\"Not_all_time_windows_have_the_same_impact\">Not all time windows have the same impact<\/span><\/h2>\n<p>The complexity of a VRPTW depends heavily on the structure of the time constraints. <strong>Wide time windows<\/strong> generally provide greater flexibility, more insertion possibilities, and a better ability to reorganise the schedule.<\/p>\n<p>Conversely, very <strong>narrow time windows<\/strong> drastically reduce the search space. In some cases, just a few critical jobs are enough to completely lock certain parts of the schedule. The optimisation engine must then deal with:<\/p>\n<ul id=\"imglist\">\n<li>high temporal density,<\/li>\n<li>extremely limited buffers,<\/li>\n<li>and much faster propagation of constraint violations.<\/li>\n<\/ul>\n<p>This temporal saturation is one of the main sources of complexity in last-mile routing operations.<\/p>\n<div id=\"attachment_128006\" style=\"width: 1610px\" class=\"wp-caption aligncenter\"><img decoding=\"async\" aria-describedby=\"caption-attachment-128006\" class=\"wp-image-128006\" style=\"border-radius: 5px;\" src=\"https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-4.webp\" alt=\"Infographic comparing a route before and after a delay. The first timeline shows a route that complies with all time windows, while the second illustrates the propagation of a 15- then 20-minute delay, reducing time buffers and increasing the risk of missing subsequent time slots.\" width=\"1600\" height=\"841\" srcset=\"https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-4.webp 1700w, https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-4-300x158.webp 300w, https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-4-1024x539.webp 1024w, https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-4-768x404.webp 768w, https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-4-1536x808.webp 1536w, https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-4-143x75.webp 143w, https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-4-700x368.webp 700w\" sizes=\"(max-width:767px) 700px, (max-width:1600px) 100vw, 1600px\" \/><p id=\"caption-attachment-128006\" class=\"wp-caption-text\">In a VRPTW problem, even a minor delay can propagate throughout the entire route, reduce the available time buffers, and compromise compliance with subsequent time windows.<\/p><\/div>\n<h2 id=\"filtering-candidate-time-slots-becomes-essential\"><span id=\"Filtering_candidate_time_slots_becomes_essential\">Filtering candidate time slots becomes essential<\/span><\/h2>\n<p>Faced with such a highly constrained search space, exploring every possible insertion would be far too computationally expensive. Before even calculating optimisation scores, the engine therefore filters candidate time slots. The objective is to immediately eliminate:<\/p>\n<ul id=\"imglist\">\n<li>positions incompatible with customer time windows,<\/li>\n<li>clearly infeasible insertions,<\/li>\n<li>or solutions likely to generate significant violations.<\/li>\n<\/ul>\n<p>As Ammar Oulamara explains:<\/p>\n<p class=\"summary-block\">\u201cFiltering candidate time slots allows computational power to be focused on insertions that are genuinely viable.\u201d<\/p>\n<p>This step is essential to maintain:<\/p>\n<ul id=\"imglist\">\n<li>response times compatible with real-time operations,<\/li>\n<li>while still preserving a high level of optimisation quality.<\/li>\n<\/ul>\n<h2 id=\"time-buffers-become-a-strategic-resource\"><span id=\"Time_buffers_become_a_strategic_resource\">Time buffers become a strategic resource<\/span><\/h2>\n<p>In dynamic routing operations, time buffers play a fundamental role. They represent the schedule\u2019s ability to absorb:<\/p>\n<ul id=\"imglist\">\n<li>traffic disruptions,<\/li>\n<li>delays,<\/li>\n<li>service overruns,<\/li>\n<li>or last-minute emergencies.<\/li>\n<\/ul>\n<p>An insertion may therefore remain technically feasible while still destroying a large portion of these buffers. The optimisation engine must not only verify the immediate validity of a route, but also its future temporal robustness.<\/p>\n<p>As Ammar Oulamara points out:<\/p>\n<p class=\"summary-block\">\u201cThe challenge is not simply to build a valid route. It is to build a route capable of surviving real-world disruptions.\u201d<\/p>\n<p>This explains why some insertions that appear geographically inexpensive are nevertheless heavily penalised.<\/p>\n<h2 id=\"time-windows-amplify-the-side-effects-of-insertions\"><span id=\"Time_windows_amplify_the_side_effects_of_insertions\">Time windows amplify the side effects of insertions<\/span><\/h2>\n<p>In a dynamic routing system, an insertion rarely affects only the route concerned. When certain time slots become saturated:<\/p>\n<ul id=\"imglist\">\n<li><strong>inter-route exchanges<\/strong> may become necessary,<\/li>\n<li>some <strong>critical resources<\/strong> can become <strong>locked<\/strong>,<\/li>\n<li>and much broader reorganisations may be triggered.<\/li>\n<\/ul>\n<p>The optimisation engine must therefore reason at the scale of the entire schedule, rather than solely at the local route level.<\/p>\n<p>This is precisely why modern optimisation engines combine multi-criteria scoring, local search, multiple neighbourhood strategies, and progressive re-optimisation mechanisms.<\/p>\n<div id=\"attachment_128012\" style=\"width: 1610px\" class=\"wp-caption aligncenter\"><img decoding=\"async\" aria-describedby=\"caption-attachment-128012\" class=\"wp-image-128012\" style=\"border-radius: 5px;\" src=\"https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-3.webp\" alt=\"Screenshot of the AntsRoute interface displaying an optimised delivery route on a map of Barcelona. The route includes multiple numbered stops connected by a purple itinerary, while a side panel details scheduled deliveries, time slots, assigned drivers, and customer information.\" width=\"1600\" height=\"945\" srcset=\"https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-3.webp 1946w, https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-3-300x177.webp 300w, https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-3-1024x605.webp 1024w, https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-3-768x453.webp 768w, https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-3-1536x907.webp 1536w, https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-3-127x75.webp 127w, https:\/\/antsroute.com\/wp-content\/uploads\/vrptw-time-windows-3-700x413.webp 700w\" sizes=\"(max-width:767px) 700px, (max-width:1600px) 100vw, 1600px\" \/><p id=\"caption-attachment-128012\" class=\"wp-caption-text\">Example of an optimised route in AntsRoute with delivery time windows that must be respected.<\/p><\/div>\n<h2 id=\"why-exact-methods-quickly-reach-their-limits\"><span id=\"Why_exact_methods_quickly_reach_their_limits\">Why exact methods quickly reach their limits<\/span><\/h2>\n<p>From a theoretical perspective, VRPTW problems belong to a particularly difficult class of combinatorial optimisation problems. As:<\/p>\n<ul id=\"imglist\">\n<li>the number of tasks increases,<\/li>\n<li>time windows become tighter,<\/li>\n<li>and operational constraints multiply,\u2028the search space grows exponentially.<\/li>\n<\/ul>\n<p>Exact methods therefore quickly become incompatible with the operational requirements of real-time environments.<\/p>\n<p>As Ammar Oulamara explains:<\/p>\n<p class=\"summary-block\">\u201cIn dynamic environments, the challenge is not simply to produce a good solution. Above all, it is about producing a robust solution quickly.\u201d<\/p>\n<p>This is why modern optimisation engines rely heavily on:<\/p>\n<ul id=\"imglist\">\n<li>heuristics,<\/li>\n<li>warm-start mechanisms,<\/li>\n<li>local search techniques,<\/li>\n<li>and adaptive exploration strategies.<\/li>\n<\/ul>\n<h2><span id=\"Conclusion\">Conclusion<\/span><\/h2>\n<p>Time windows fundamentally transform route optimisation problems because they introduce strong temporal dependencies, propagation effects, waiting times, local saturation, and robustness constraints that are far more difficult to manage.<\/p>\n<p>In a VRPTW, a route must therefore do more than simply minimise geographical distance. It must also preserve time buffers, maintain the ability to absorb disruptions, and remain stable enough to operate effectively in a dynamic environment.<\/p>\n<p>It is precisely this temporal dimension that now makes VRPTW one of the most complex challenges in last-mile logistics.[\/vc_column_text][\/vc_column_inner][vc_column_inner el_class=&#8221;vc_hidden-xs Extra Small Screen vc_hidden-sm Small Screen&#8221; width=&#8221;2\/12&#8243;][\/vc_column_inner][\/vc_row_inner][vc_row_inner][vc_column_inner width=&#8221;2\/12&#8243;][\/vc_column_inner][vc_column_inner width=&#8221;8\/12&#8243;][vc_separator color=&#8221;custom&#8221; accent_color=&#8221;#00041f&#8221;][vc_column_text css=&#8221;&#8221;]\n<p class=\"text-head\" style=\"color: #424762;\">WRITTEN BY<\/p>\n<p><img decoding=\"async\" class=\"alignnone size-medium wp-image-85398\" style=\"border-radius: 100%;\" src=\"https:\/\/antsroute.com\/wp-content\/uploads\/marie-henrion-antsroute-300x300.jpg\" alt=\"\" width=\"70\" height=\"70\" srcset=\"https:\/\/antsroute.com\/wp-content\/uploads\/marie-henrion-antsroute-300x300.jpg 300w, https:\/\/antsroute.com\/wp-content\/uploads\/marie-henrion-antsroute-150x150.jpg 150w, https:\/\/antsroute.com\/wp-content\/uploads\/marie-henrion-antsroute-146x146.jpg 146w, https:\/\/antsroute.com\/wp-content\/uploads\/marie-henrion-antsroute-50x50.jpg 50w, https:\/\/antsroute.com\/wp-content\/uploads\/marie-henrion-antsroute-75x75.jpg 75w, https:\/\/antsroute.com\/wp-content\/uploads\/marie-henrion-antsroute-85x85.jpg 85w, https:\/\/antsroute.com\/wp-content\/uploads\/marie-henrion-antsroute-80x80.jpg 80w, https:\/\/antsroute.com\/wp-content\/uploads\/marie-henrion-antsroute.jpg 416w\" sizes=\"(max-width:767px) 70px, 70px\" \/><\/p>\n<p class=\"text-head\"><span style=\"font-size: 25px;\"><strong><a style=\"text-decoration: none;\" href=\"https:\/\/antsroute.com\/en\/blog\/author\/marie-henrion\/\">Marie Henrion<\/a><\/strong><\/span><br \/>\nAt AntsRoute, Marie has been the marketing manager since 2018. With a focus on last-mile logistics, she produces content that simplifies complex topics such as route optimization, the ecological transition, and customer satisfaction.<\/p>\n<div id=\"cta\"><a class=\"button-3\" href=\"https:\/\/www.linkedin.com\/in\/mariehenrion54\/\" target=\"_blank\" rel=\"noopener\">in<\/a><\/div>\n[\/vc_column_text][\/vc_column_inner][vc_column_inner width=&#8221;2\/12&#8243;][\/vc_column_inner][\/vc_row_inner][\/vc_column][vc_column width=&#8221;1\/12&#8243; el_class=&#8221;vc_hidden-xs Extra Small Screen vc_hidden-sm Small Screen&#8221;][\/vc_column][\/vc_row][vc_row el_class=&#8221;padding-block&#8221; css=&#8221;.vc_custom_1705329750413{background-color: #00041f !important;}&#8221;][vc_column][vc_column_text css=&#8221;&#8221;]\n<p class=\"h2-footer\" style=\"text-align: center; color: #ffffff;\">Optimise your Routes with AntsRoute.<\/p>\n<p class=\"text-head\" style=\"text-align: center; color: #bfc0c6;\">Free 7-day trial | No credit card required<\/p>\n[\/vc_column_text][vc_row_inner][vc_column_inner][vc_column_text]\n<div id=\"cta\" style=\"text-align: center;\"><a class=\"btn-grad\" style=\"align-self: center;\" href=\"https:\/\/app.antsroute.com\/subscription\/creation\" target=\"_blank\" rel=\"noopener\"><strong>Get started<\/strong> \u2013 It&#8217;s free<\/a> <a class=\"button-2-white\" style=\"align-self: center;\" href=\"https:\/\/calendly.com\/lea-brice-antsroute\/demonstration\" target=\"_blank\" rel=\"noopener\">Book a demo<\/a><\/div>\n[\/vc_column_text][\/vc_column_inner][\/vc_row_inner][\/vc_column][\/vc_row]\n<\/div><div id=\"toc_container\" class=\"toc_wrap_right no_bullets\"><p class=\"toc_title\">Contenu<\/p><ul class=\"toc_list\"><li><a href=\"#A_VRPTW_route_is_no_longer_just_a_distance_problem\">A VRPTW route is no longer just a distance problem<\/a><\/li><li><a href=\"#Time_propagation_completely_changes_the_nature_of_the_problem\">Time propagation completely changes the nature of the problem<\/a><\/li><li><a href=\"#Waiting_times_significantly_reduce_route_efficiency\">Waiting times significantly reduce route efficiency<\/a><\/li><li><a href=\"#Not_all_time_windows_have_the_same_impact\">Not all time windows have the same impact<\/a><\/li><li><a href=\"#Filtering_candidate_time_slots_becomes_essential\">Filtering candidate time slots becomes essential<\/a><\/li><li><a href=\"#Time_buffers_become_a_strategic_resource\">Time buffers become a strategic resource<\/a><\/li><li><a href=\"#Time_windows_amplify_the_side_effects_of_insertions\">Time windows amplify the side effects of insertions<\/a><\/li><li><a href=\"#Why_exact_methods_quickly_reach_their_limits\">Why exact methods quickly reach their limits<\/a><\/li><li><a href=\"#Conclusion\">Conclusion<\/a><\/li><\/ul><\/div>\n","protected":false},"excerpt":{"rendered":"<p>Discover why time windows make VRPTW problems far more complex: delay propagation, waiting times, time buffers, and dynamic route optimisation.<\/p>\n","protected":false},"author":9,"featured_media":128000,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[22963,22934,6282],"tags":[],"class_list":["post-127992","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog","category-route-optimisation","category-solutions"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v19.0 - 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