This article presents the results of optimizing the reliability and reliability of the time forecast’s development reserves of the coal mine long wall areas and the preparation time of the face longwall line. A scheme of the reproduction the long wall front process in the form of a decision tree model has been developed. The dependences of the optimal probability of the absence of coal mining losses and the optimal dynamic time reserve on the reliability of longwall and preparatory work and on the ratio of damage in case of shortage, as well as the costs of maintaining the cleaning front, are established. It is shown that when forming a mining development plan, the value of the optimal dynamic time reserve should be determined for each treatment face. It is determined that when providing dynamic redundancy of the process of reproduction of the longwall front, the possibilities of performing degassing and drainage of mineral reserves being prepared for extraction are more fully realized which positively affects the level of reliability and safety of longwall operations.