Boeing has issued this statement:
Boeing is pleased that Singapore Airlines has announced its commitment to purchase 20 777-9s and 19 787-10 Dreamliners. The national carrier and 787-10 launch customer also announced its recommitment for its previous order for 30 787-10 airplanes.
The 787-10 is the third member of the super-efficient, passenger-pleasing 787 Dreamliner family. With its greater passenger and cargo capacity, high degree of commonality and passenger-pleasing features.