https://wccftech.com/free-metro-exodus-update-xbox-available/

The free Metro Exodus next-gen update already appears to be available for Xbox Series X|S player owning the game on last-gen consoles.

The update was supposed to become available tomorrow alongside the retail release of next-gen versions, but it seems that the “release Xbox Series X|S update” button was pushed somewhat earlier. Xbox Series X owners are required to download 66.96GB of new data, although we haven’t been able to verify whether this also applies to the Xbox Series S version of the game.