Actually according to police rules P/ASI should be promoted to SI after 3 years, only if seats are available for promotion. It will be decided by departmental promotion comity (DPC) that who is eligible and who is not.

Perks and privileges for ASI.
1) High pay compared with employees of grade 9 in other department.
2) Govt quarter for police families.
3) Police having great role in our society , therefor, ASI can play his prestigious role in maintenance of law and order in society.

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