Cut and pasted from one reliable source with no editing done:
"This is an exercise planned by Airbus Industrie OVER TWO MONTHS ago.
A 15 hour non-stop return flight From and To Manchester by the A340-600.
To test, prove and demonstrate what this new aircraft can do. And also as a 'Thank You' to the BAE employees at Chester who built the wings, some of whom are on board.
Manchester Airport is also taking the opportunity to size up the new aircraft with regards to airport terminal infrastructure, stands and taxiways etc."
David (500m visibility still forecast