In January 2017, the Nintendo 3DS downloadable software Pokémon Bank is expected to receive an update for compatibility with Pokémon Sun and Pokémon Moon. Pokémon Bank is an application that enables you to put Pokémon you’ve collected in your games into Internet-based storage boxes. Until now this service has been available for Pokémon Omega Ruby, Pokémon Alpha Sapphire, Pokémon X, and Pokémon Y. Starting in early 2017, it will support Pokémon Sun and Pokémon Moon as well.
With this update, the Pokémon that adventured with you in Pokémon Omega Ruby, Pokémon Alpha Sapphire, Pokémon X, and Pokémon Y will be able to join you in Pokémon Sun and Pokémon Moon!