Originally Posted by skunker

Had the following back on 9 March, LIN-LHR-MIA-SAN. First two legs BA metal with BA codes, last leg AA code and AA metal. BA did their job and got me to MIA only a little late; however, AA did not. First the flight to SAN was delayed and ultimately canceled, but I was transferred over to a later flight and downgraded to economy from first. The later flight was delayed and we didn't arrive into SAN until 5:15am 10 March instead of my original 9:44pm 9 March. AA did a refund of about $95 for the downgrade and 5000 miles for the delay, but reading EC261 it looks like they should be on the hook for a lot more.

1) Does EC261 or UK261 apply for the domestic connection?
2) How would I apply for compensation against AA?
3) AA claimed I'm not due anything because of ATC issues at MIA, but I have screenshots showing the original plane had arrived and expertflyer showed delay was due to crew availability. Later flight was ground handling issues and mechanical delays, which AA chat at the time confirmed. Can they claim extraordinary circumstances that broadly?