Section 14(1) in The Assam Economic and Statistical Service Rules, 1973
(1)All persons appointed to the different categories of posts in the Service against permanent vacancies shall be on probation for a period of 2 (two) years:Provided that the period of probation may, for good and sufficient reasons, be extended by the Governor in individual cases by a period/periods not exceeding two years:Provided further that the Governor may reduce the period of probation to one year for those who have already passed all the Departmental Examinations as prescribed for the Service:Provided further that the Governor may at his discretion-(a)count any period of service in posts carrying equivalent or higher responsibilities;(b)count in the case of persons promoted from a lower category, the period of officiating service, if any, towards the said period of two years.
