Starting with the Pokémon TCG: Sun & Moon—Guardians Rising expansion, stores in the U.S. and Canada that host Play! Pokémon Prerelease tournaments will be allowed to sell products on the Monday before the official release date. For example, the launch date for the upcoming Sun & Moon—Guardians Rising expansion is Friday, May 5, so these stores can begin selling booster packs, theme decks and other Sun & Moon—Guardians Rising products on Monday, May 1.
Source: Pokemon.com
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