bearing in mind where the aircraft and the slots for this service are coming from, i think that you'll find that this is the exact rotation/slot usage of the current shannon operation.
aircraft overnights in heathrow for the winter, and in shannon....soon to be bfs, in the summer. first shannon flight in the winter is 0740, in the summer its 0850
this has always seemed like a strange time in the evening for a flight, probably more to do with the use it or lose it scenario with lhr slots, than with passenger needs.