20 hours Layovers at Heathrow and Dublin airports. Do I require transit visa for both?

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.

TRANSIT VISA AT BKK AIRPORT

I have booked THAI AIRWAYS flight from NEW DELHI TO TAIPEI (Layover in BKK),

My onward ticket has two flights: 1) NEW DELHI to BANGKOK Suvarnabhumi (23:30 – 05:30) 2) BANGKOK Suvarnabhumi to TAIPEI (07:10 – 11:50) Layover time: 01 hrs 45 minutes

My return ticket has also two flights: 1) TAIPEI to BANGKOK Suvarnabhumi (14:05 – 16:50) 2) BANGKOK Suvarnabhumi to NEW DELHI (17:55 – 20:55) Layover time: 01 hrs 05 minutes

Can anyone tell me how to manage the timings and do i need a transit visa in BKK?

Does a student need transit Visa in London [duplicate]

This question already has an answer here:

  • Is there a way to find out if I need a transit visa for a layover in the UK? 2 answers

I am a student and I am travelling from India to USA. I am on F1 visa and my layover is in London of 17 hours. My flight is American airlines and will reach in London airport at 3:20pm and depart next day at 7am from same airport.

Do I need a transit visa ?