I hold an Indian Passport.
I am traveling from Mumbai to Washington DC via the British Airways flight which has two layovers: 16 hours in London and 4 hours in Dublin. I possess an F-1 US student visa. I would be reaching London at 18:25 p.m. and would depart for Dublin at 6:30 a.m. the next day. Similarly, I would reach Dublin at 8:00 a.m. and depart for Washington DC at 12:00 p.m.
I would also need to change terminals at Heathrow from Terminal 5 to Terminal 2.
I wanted to know whether I would require a transit visa for both the places as I am not able to get proper information about the requirements from the official pages. Reading the pages only show that you can transit without a visa if you hold an itinerary to your destination and hold the visa for the US.
Please help me as I am confused and don't want to get in trouble at international airports.