Where it comes from
Pokémon TCG Standard Format Rotation Announced for April 10, 2026 PokeGuardian · 9 January 2026 Open the original ↗
The line in the source
Every Championship Series season, Play! Pokémon removes older cards from competition in the Standard format with the goal of maintaining a healthy competitive environment.
In English
The rationale is formats/rotation, i.e. the library is deliberately kept in a rolling window; Legendary Collection (2002) and later Expanded format keep old cards playable.