State-owned Air India has extended its offer of upgraded travel in executive class on its domestic network to 45 airports. Earlier the offer was available only in 17 airports.A press release of Air India in Mumbai said the offer is open to all passengers holding economy class tickets including APEX fares and would remain valid till June 30 .The release said under the airline's on-going airport upgrade scheme,passengers flying on economy class ticket can upgrade their tickets to executive class at theairport by paying a fixed amount.The airline said the airport from where passengers can avail the upgraded facility include Chandigarh, Gwalior, Jaipur, Ahmedabad, Pune, Coimbatore, Tirupati, Bhubaneswar, Imphal, Ranchi among others.