Pokémon UNITE has announced that from November 1st, 2024 until December 5th, 2024 at 3:59 UTC, all players that login at any time during the distribution period, can receive a Pokémon TCG Pocket commermorative Unite snapshot background. A popup during login appears that allows players to claim the background.
To commemorate the release of Pokémon TCG Pocket, we're giving away a special Trainer background to everyone who logs in to Pokémon UNITE! Available until December 5 @ 3:59 UTC
Source:
https://x.com/PokemonUnite/status/1852427873019191728