<p>In today’s dynamic business landscape, sustainable and flexible supply chains are crucial for organizational resilience and responsiveness. Among the key adaptive strategies that firms employ are demand-stimulating mechanisms, such as sales promotions, often initiated to manage inventory levels and accelerate the market penetration of innovative products. While these strategies are often pre-planned, unpredictable demand surges necessitate supply chains that can respond quickly. Adopting the dynamic capability view as its conceptual lens, this study examines Indian automotive supply chains to identify and analyze the critical success factors for achieving sustainable supply chain flexibility to manage demand surges during these adaptive options. Applying the best–worst method cum DEMATEL, along with the sensitivity analysis conducted, the research presents data-driven insights. Findings from both methodologies highlight that sustainable manufacturing, sustainable sourcing, and volume flexibilities play a key role in enabling organizations to meet promotional surges while maintaining sustainability, underscoring their importance as core dynamic capabilities for competitive advantage. This study offers practical insights for enhancing sustainable responsiveness to demand surges, focusing on the automotive sector. It progresses the conceptualization of sustainable supply chain flexibility as rapid, sustainable adaptation to promotional demand fluctuations and applies a combined BWM-DEMATEL methodology to strengthen research in this evolving domain.</p>