I have already replied to a similar question. Please see: Service matter – whether railway employees are Central Govt civil servants.
Please see this Notification from the Staff Selection Commission (SSC) for eligibility for the Combined Graduate Level Examination (CGL) which also gives details of age relaxation for various categories, including the Central Govt. Civilian Employees. In my personal opinion (due to the reasons given in my above answer), you should be in a position to claim the age relaxation benefit under this category. However, to get an accurate answer, please contact the SSC for clarification, since I am not aware what meaning they are giving to the expression “Central Govt. Civilian Employees”. If needed, file an RTI application with SSC. Further, if needed, you can even consider approaching the Central Administrative Tribunal, after weighing all the pros and cons.
Dr. Ashok Dhamija is a New Delhi based Supreme Court Advocate and author of law books. Read more about him by clicking here. List of his Forum Replies. List of his other articles. List of his Quora Answers. List of his YouTube Videos.