Without going back to look, I believe that in other seasons with stops in India, teams frequently had to get to Mumbai to get out of India, and often had to go to Dehli from elsewhere to do that. Conversely when teams were on a west-to-east route through India, teams often had to fly into Mumbai in order to connect to other locations in India.
Bottom line: except when Mumbai is the destination, teams often have had to fly in or out of Mumbai to get elsewhere.