After more than nine years of operation, the Pokémon Global Link (PGL) service will be retired on February 24, 2020, at 23:59 UTC. After PGL service has ended, you will no longer be able to use any gameplay features that require a connection to the PGL on your Pokémon Ultra Sun, Pokémon Ultra Moon, Pokémon Sun, or Pokémon Moon games. You will still be able to use other online functionality apart from the PGL.
Pokémon Sword and Pokémon Shield will provide services similar to the PGL’s Rating Battles and Online Competitions features and will be available to play via Nintendo Switch.
Source: Nintendo.com
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