The term "schedule operation" can be easily substituted with a number of synonyms depending on the context and industry. In the medical field, "planned surgery" or "prearranged procedure" are commonly used instead. In the manufacturing industry, "planned maintenance" or "scheduled maintenance" can be used. In the transportation industry, "timetabled operation" or "scheduled service" could be appropriate. Other similar phrases that can be substituted for "schedule operation" could include "pre-planned process," "preset engagement," or "anticipated activity." Ultimately, the most fitting synonym will depend on the specific industry and circumstances involved.