New Delhi, Oct. 26 -- After weeks of holding out against shifting flights from Mumbai to Navi Mumbai, IndiGo and the Air India Group have become the first carriers to announce plans to move some operations to the new airport, paving way for the redevelopment of Terminal 1 (T1) at the city's existing airport. Together, they will shift 133 weekly international departures to the new airport 50 km away by July, marking a breakthrough in a standoff with operator Adani Airport Holdings Ltd, according to a person aware of the matter. The standoff, which saw airlines resist the plan to shift and question capacity curbs at Terminal 2 (T2), prompted the civil aviation ministry's intervention and a string of exchanges between the airport operator and carriers. IndiGo will shift 84 weekly departures, while Air India Group-Air India and Air India Express-will move 49, said a person aware of the talks....