Nowadays, the vast majority of industrial processes are automated including all of the control levels from field devices to production scheduling. However, in critical infrastructures like nuclear power plants (NPPs), the air gap separates the first three levels of field, control, and supervisory from the last ones and largely terminates the direct control at the supervisory level making it the upper point of an industrial control system at which data from lower levels are collected, processed, and presented as well as commands to the lower-level devices are given. For NPPs, it is the upper level control system (ULCS). Being the top integrated stage of industrial control, the ULCS operates with a substantial amount of information: signals, alarms, commands, etc. As a result, the ULCS application software, which comprises all of this information accompanied with basic visualization tools, happens to be incredibly complicated and absolutely huge; moreover, it is not invariable and subjected to changes during the whole ULCS life cycle. A complex problem of making changes to the ULCS applica-tion software arises. Due to the enormous complexity and substantial amount of information, the automation of making changes is required. The article is devoted to the ULCS application software and the issues related to making changes to it; particularly, the automation of making changes is considered. The overview of the ULCS application software is presented. The methods for automated making changes are revealed. A system for the data preparation for making changes is clearly outlined: functionality, common structure, and software composition.