Flybywire
Maybe it's in my mind from phoning them, I'm not sure? On a recent flight I'm pretty sure they either played the delibes piece or the other 'BA theme tune' by Verdi (I think), which they used in Ads quite a few years ago.
Anyway, the marketing folks must be pleased, I think of BA, and I think of the flower duet. Which is quite sad, really..