The European Union plans to double the freight rail traffic by 2050 both to cut pollution emissions and to mitigate congestion by shifting traffic from road to rail networks. One of the challenges is to minimize emissions and high costs associated with shunting yard operations while maintaining an acceptable service level. In this context, we propose an Event-Based Simulation Framework for wagon Shunt-in and Shunt-out operations. The Event-Based Simulation Framework exploits programming tools and a MILP model to minimize the number of Shunt-in and Shunt-out operations performed and, consequently, both strategic and tactical objectives such as the wagon fleet size, departure delays and emissions of shunting locomotives. Several versions of the MILP model are described based on the Shunt-in policy applied. Each Shunt-in policy has different criteria for wagon's choice and has shown a strong goal orientation. To test the MILP model's effectiveness, we have considered short and long-term real train timetables for freight trains in the Bettemburg Eurohub Sud Terminal (Luxembourg) and we have assessed different KPIs linked to tactical and strategic objectives. Computational results show that the criteria for choosing which wagons should be taken-out from the inbound train and should be inserted into the outbound train might significantly impact multiple rail system KPIs analyzed. The Event-Based Simulation Framework is part of the ANTOINE national project financed by CFL (Chemins de fer luxembourgeois) and is considered an add-on tool to Shunty, an industrial software project for rail decision-makers.