Update for Asia/Calcutta timezone

I seek to update the name of the Asia/Calcutta timezone (+0530 UTC). Why Calcutta was chosen in 1970 when Calcutta was India's most most populated city. Since then, - Calcutta has been renamed Kolkata (2001) - Mumbai (formerly Bombay) overtook Calcutta as India's most populous city (1991 census) Note: Time in India is calculated from Mirzapur near the city of Allahabad. I seek to change the name of the timezone to - Asia/Mumbai (based on the most populous city) OR - Asia/New Delhi (capital of India, second most populated, more centrally located) Regards, Nicholas