The top hierarchy of the armed forces is set for a change. The Chief of Defence Staff, Gen Anil Chauhan, Army Chief Gen Upendra Dwivedi and Navy Chief Admiral DK Tripathi are set to end their tenures in the coming months.The CDS and the Navy Chief retire at the end of May, while the Army Chief retires on June 30.An officer appointed as CDS retires at 65, while the age of superannuation for the Army and Navy Chiefs is 62 years.This means three top posts — all four-star rank appointments — will require decisions from the government in the coming weeks.In the Army, a reshuffle ahead of the expected change at the top has already been carried out. Southern Army Commander Lt Gen Dhiraj Seth has been appointed as the Vice-Chief of the Army. He will be the senior-most officer after Gen Dwivedi, and analysts see his posting to the Army Headquarters as preparation for a larger role at the top.Lt Gen Seth, from the Armoured Corps, is scheduled to replace the current Vice-Chief Lt Gen PP Singh on April 1. Lt Gen Singh will move to the Western Command headquartered at Chandimandir. The command faces westwards and has corps at Ambala, Jalandhar and Yol near Dharamsala in Himachal Pradesh.Lt Gen Sandeep Jain, Chief of Staff at Southern Command, has been promoted to the rank of Army Commander. He will replace Lt Gen Seth at Southern Command, headquartered in Pune. The command also faces westwards and oversees two key corps — one headquartered at Jodhpur and the other at Bhopal.Lt Gen VMB Krishnan has also been promoted to the rank of Army Commander and will be the next Eastern Army Commander. He will assume charge on April 1, replacing Lt Gen RC Tiwari. The command’s operational area includes the entire North-East, West Bengal and Sikkim.For the post of CDS, the government can appoint a serving service chief or a retired three-star officer in the rank of Lieutenant General or equivalent. Gen Chauhan was appointed to the post after his retirement.For appointing a retired officer as CDS, the existing rules define that the officer should have attained 62 years of age.Three-star officers in the armed forces retire at the age of 60.The government is pushing for greater jointness and integration among the three services, and ensuring this coordination is the primary role of the CDS.