I am a student, intending to travel from Ahmedabad to Toronto, Canada via Jetairways on 18th of April. My query is that for this journey the connecting flights are from London, Heathrow Airport. So do I need a Transit Visa for the UK? Or I can travel without it and just pass throw the airport terminals? For the onward journey, my terminal is changed in London from 4 to 2. Please advice.