A340-300 - Seat Selection

Hi,
So the seat reservation is now available for my flight to Boston August 2015, and its showing an A340-300, but surely these are leaving the fleet before August next year?
I'm travelling UC so doesn't really bother me, but can't imagine people paying for their preferred seating being happy that the type of plane must change before departure
Or am I missing something here?
thanks

So the seat reservation is now available for my flight to Boston August 2015, and its showing an A340-300, but surely these are leaving the fleet before August next year?
I'm travelling UC so doesn't really bother me, but can't imagine people paying for their preferred seating being happy that the type of plane must change before departure
Or am I missing something here?
thanks
