## 2 Fundamental Definitions  
In the literature, there are dozens of methods that support the prediction of future sales [27]. The final goal of a demand plan is to provide accurate future demand to support decision-making [28]. Demand types are commonly classified as stationary, seasonal, trend-based, and sporadic demand [29]. Forecast, then, is key for good planning. However, if this planning is not accurate, then all the downstream resource planning--personal, technical, or material--will also not be accurate. Therefore, higher investments and costs will be the result, along with lower customer service level. To prevent this from happening for organizations, the scenarios with higher and lower probability must be assessed [30]. Other researchers described the need to develop models for forecasting demand and evaluating policy scenarios for meeting optimistic and pessimistic future demand projections using a system dynamics framework to generate scenarios because of its capability to understand nonlinear dynamic behaviors in uncertain conditions [31]. Statistical treatments, as changepoint techniques, support the detection of abrupt changes in data series to highlight shifts in the system conditions, such as rainfall for climate conditions [32]. Moreover, to deal with various scenarios, managing uncertainty is key to success. In this context, the detection of structural changes in data series is a fundamental problem in statistics with multiple applications by seeking to estimate when the changes occur and the value of those changes with a changepoint analysis [33]. Sometimes supply chain management (SCM) and logistics are used as synonyms, although SCM includes a broader meaning than logistics [34]. The areas of logistics management include procurement, production, and distribution [35]. The supply chain components include all parties involved, directly or indirectly, in fulfilling a customer request. The supply chain includes not only the manufacturer and suppliers but also transporters, warehouses, retailers, and even the customers themselves [36]. Logistics management is focused with optimizing flows within the organization, while SCM recognizes that internal integration by itself is not enough [4]. A closer integration and a better coordination of material, information, and financial flows of the organizations along the supply chain is needed. To achieve that, aligning strategies, dealing with organizational barriers, and improving flows along the supply chain are fundamental areas of SCM [28]. Therefore, SCM is about the management of relationships across networks of companies that are legally independent and have interrelationships among them [4]. Therefore, SCM can be defined as the task of integrating organizational units along a supply chain and coordinating materials, information, and financial flows to fulfil end-customer requirements and improve the competitiveness of the whole supply chain [28]. Specific goals that are desirable include low stocks, short leads and reaction times, reliable delivery service, punctuality, complete delivery, and high delivery flexibility. However, between those goals, there are irremediable conflicts. As a consequence, not all goals can be reached equally [1]. From these conflicts, challenges emerge for supply chain management, including how to deal with the corporate conflicts of goals, the conflicts of goals between the different stages within the supply chain, and the lack of transparency between the units in a supply chain [1]. In this context, S&OP has existed, in principle, as far back as the 1980s, and emerged out of what was known as materials requirements planning [23]. S&OP aims at balancing supply and demand and aligning strategic and operational plans on a tactical planning horizon of typically 3-24 months. S&OP comprises a five-step process: product planning, demand planning and supply planning, and, finally, a pre-S&OP meeting and an executive-S&OP meeting for decision-making at different hierarchical levels regarding the supply-demand balance [22].