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I am an Indian Citizen traveling to Montreal, Canada via LHR airport on a study permit. My layover at LHR(London-Heathrow) is 20 hours which goes to the next day. Consequently, I'll have to recollect my entire checked in baggage and get it rechecked for the next flight which binds me to go through the immigration again.
I wish to ask if I would need a transit visa or any other such document?