This study addresses the optimization of diluent allocation in the production system of an extra-heavy oil reservoir, focusing on enhancing efficiency and operational stability. The research was motivated by the challenges faced in managing the M Block project, where improper dilution ratios led to inefficiencies such as high back pressure, reduced production capacity, and increased operational complexity. By conducting a comprehensive review of field data and implementing advanced computational models, we identified key factors influencing the distribution of diluent across multiple platforms. To achieve optimal results, the study proposes an innovative framework for determining the ideal dilution ratios based on platform-specific characteristics and operational constraints. Through detailed simulations and comparisons of different scenarios, we demonstrate how adjusting diluent allocation can mitigate issues like excessive back pressure in distant platforms while maintaining consistent API values throughout the system. This approach not only ensures efficient resource utilization but also minimizes downtime and operational challenges. The study highlights that implementing a unified dilution ratio across all platforms ensures consistent API of 16 at various points, including the export, along the pipeline, and at the oilfield exit. However, this approach leads to high back pressure in remote platforms, resulting in reduced production pressure differential and lower productivity. To mitigate these challenges, a refined strategy was proposed to optimize dilution ratios based on platform-specific conditions, ensuring balanced production efficiency without compromising operational stability. Field observations revealed that the strategic placement of flow meters and pneumatic control valves at each branch effectively managed flow distribution and maintained desired pressures. Furthermore, the study underscored the importance of economic optimization by reducing unnecessary diluent usage while achieving stable production performance. These findings provide actionable insights for improving production systems in heavy oil reservoirs, particularly under conditions of limited diluent availability. The proposed strategies offer a practical framework for enhancing productivity, operational efficiency, and sustainability in large-scale heavy oil fields. The proposed strategies have direct applications in similar heavy oil fields worldwide, offering significant benefits for operators seeking to maximize efficiency while reducing operational complexities. This research thus represents a valuable addition to the technical knowledge base of petroleum engineering, particularly in the context of resource optimization and production system management.