When you pass ASI test from commission your seniority is determined by commission. If you are first in commission you will be first in seniority among group. For 3 years you will be on probation period means you will be PASI. After 3 years you will be confirmed by department as ASI and will be eligible for promotion of SI. During 3 years of probation you will go through different training and courses which are as follow.
1) Training= 1 year
2) A course= 3 months, which you spend in prosecution branch and you will learn how police prosecutes different cases
3)B course=2.5 months, which you will spend in police line and you will perform duties of different kinds and spend time in different offices
3)C course= 15 days, which you will spend in CCPO office and learn duties of different offices
4) D course= will be in two parts in which you will spend 6 months in operation duties and 12 months in investigation duties.

Remember after compilation of each course you have to take test. And after passing you will get entered in other course. Course duration may vary.

Hope you have got it.

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