3-month revision plan for UPSC Prelims 2021? All you need to know Here is an exam — cracking, 3 months revision plan for UPSC Prelims 2021. advertisement 3-month revision plan for UPSC Prelims 2021? All you need to know The civil services' examination is the key to a career in the most coveted government services in the country. Every year, lakhs of candidates sit in the examination to fulfill their aspirations. With less than three months to go for its preliminary examination, it is an extremely crucial period for the UPSC aspirants. A proper strategy during this period can see you through the first, screening stage and enable you to reach the next frontier- the main examination.