When aeroplanes are delayed during the warm, rainy season that causes smog, accept it and take it in your stride. This will help you to enjoy your trip, especially your arrival and departure.
Plan for a 2-part departure, flying the first leg from Bangalore to Mumbai in the evening, with an 11 am flight from Mumbai to Heathrow the next morning. Therefore, any delays will not have you queueing for hours having been up since the crack of dawn with a short fuse for an international departure. Also warn your hotel if there is a chance that you may need accommodation, in the event that you cannot depart.
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