Agree with Mike.
From memory both the 787/A350 are meant to fly about 8000nm and 250-280 seats.
However, the A350-1000 is reported to seat 350 passengers and fly 8000nm.
This would/could be a 747 replacement
As much as I "hate" to say it a fleet of all A350 would be better say tha -800 and -1000 series. As Boeing still have no confirmed a larger 787 yet
Perhaps the 787 order was just to keep Boeing happy