The 787 is due ''early'' next year . . .
The Boeing 767 is used for all long-haul flights. I don't know where the heck you would hear such a rumour that the 738 would be operating the flight though!
Talking to Swissport dispatcher who had offloaded a 738 that had done CUN-LGW with a tech stop, which he said was because of low load factor on the route. It sounded unbelievable but I thought I'd ask the Q..