I'm in the beginning stages of planning a trip this summer and have been looking at airlines and fares for my proposed route. It appears as if EI is the cheapest airline for my dates across the Atlantic taking me from JFK to LHR via DUB and back to JFK from MAD, again via DUB.
Upon arrival in LHR I'd be transferring onwards to IST on either Turkish. I'd be aiming to take the 11:25 departure to IST on TK because the flight is operated by the A330-200.
I am aware that EI is in T1 and TK is in T3 and that upon arrival in LHR I'd have to recheck in my luggage with TK.
My question is does anyone know how much time I should leave between the transfer? The EI flight would arrive in LHR at 8:05am. Do I go through immigration at DUB or would I have to do it at LHR?