Dreamliners were supposed to go into service (not with BA, but ANA) in 2008 if I remember correctly? Finally flew commercially in late October 2011. They would have originally been delivered to BA in 2010 so a 3 year delay on that one.
The A380 was a lot more managed delay I think but it will be eventually about 2 years behind the scheduled EIS if I remember rightly?
Help on this one very, very much appreciated! Ed