The correct answer is 2020. According to a report in Dainik Statesman. ATK Mohun Bagan will reportedly be renamed back to Mohun Bagan FC. On July 10 2020, ATK FC merged its brand with the football section of Mohun Bagan AC to form ATK Mohun Bagan FC. Since the merger with ATK, the Kolkata-based franchises fans have expressed their discontent with the name and showered disagreement across social media platforms. The Mariners have competed in the Indian Super League (ISL) for two seasons under their new name ATK Mohun Bagan, finishing runners-up in their first season and reaching the semi-final stage in the next season. Additional Information Football Association ( IFA) has given permission to Diamond Harbour Football Club (DHFC) and Belghoria Athletic Club to play in first division TMC MP Abhishek Banerjee launched Diamond Harbour Football Club (DHFC), the club hails from his constituency Diamond Harbour. Krishnendu Roy has been appointed as Coach for the team. The Football club will play a first division Calcutta league match.