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I am travelling from India and have 7.5 hours of layover at Heathrow airport for my connecting flight to Canada. I am arriving on terminal 4 and connecting flight departs from terminal 2. In the meantime of my layover a few of my friends wants to visit me at the airport so do I need DATV to meet them personally? Or is it possible to meet friends at the airport without any transit visa as I am not going out of the airport premises. Do I have to collect my bags and recheck-in if I have DATV? Is there any other possible way to spend the layover time with my friends at the airport?