Promotion Matter

- my self working in a PSU name NHPC Limited. - Joined as Junior Engineer(Mechanical) in 2001. - Corporation had a policy of promotion to Assistant Engineer post, after completion of 10 years service, followed by written exam,Interview and subject to Vacancy. - Got Promoted to Assistant Engineer(Mechanical) with effect from 01.04.2012, following above promotion procedure. - Corporation revised its policy for promotion in the year of 2014, i.e. promoting all Junior engineers to Assistant Engineers who have competed 10 year of service, and the hurdle of written exam,Interview and subject to Vacancy had been extended to next promotion, i.e. Engineer. - I have not got any benefit of the revised policy. though i have been compelled for the same clear same hurdle at next promotion of Engineer. - I have appeared in written exam for next promotion of Engineer on 05.03.2017. I have qualified written exam, then appeared before interview. - No vacancies were disclosed before for this promotion exam. - In the final promotion list, I could not be promoted because of vacancy constraint. - I had complained in corporation Grievance Cell and also sough RTI, - I got information that vacancy were only 4, hence best 4 has been selected, and i could not got promotion.(8 candidates cleared exam) - please guide me what could be done in this case, because i have not got any benefit of new policy, no vacancy were disclosed for promotion exams. and whether it is right to clear the same hurdle again and again, as corporation changed its policy?