The thing is that Air India was well aware about the delay in Dehlhi already when I was in waiting in Pune / PNQ. Air India could have put me on a (LH) flight from PNQ to FRA with a connection to LHR, and then I would have arrived in London without delay. Instead - to save money - Air India deliberately let me arrive late in Delhi with no chance to connect to LHR, so I ended up missing a day in London.