It took me a year to receive the EU261 comp from Iberia following a 4 hour delay from LHR>MAD which ruined the start of my weekend. They claimed extraordinary circumstance "due to delays caused by previous stopover" or "technical fault which our technicians had to resolve to ensure safety of the flight". I think we went back and forth at least four times before reporting to AESA. They wouldn't entertain the claim as the flight originated in London. CAA weren't much help either as they sent a standard " we are contacting Iberia and will respond when they have responded". I kept persisting and lo and behold 1 year minus 5 days from the delayed flight they agreed to pay the 250 euros. You have to be persistant. Although i would argue 250 euros was not worth the time and effort i spent across the year....