Pokémon Sleep will undergo maintenance from May 20 to May 21 as the game prepares for the rollout of version 3.5.0. The update is set to introduce new features, balance adjustments and other improvements aimed at refining the overall gameplay experience. Players can also expect temporary downtime during the maintenance window while the new version is applied across the app.
Source: Official Pokémon Sleep news and PokemonSleep.net
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