For one-day tickets that are valid for any time within the Expo period, the Super Early Bird Discount is avaible until 6 October 2024 for JPY￥6,000. The Early Bird Discount is available between 7 October 2024 to the day before the opening day for JPY￥6,700, making it cheaper to purchase a ticket before the opening day. Please note that Opening tickets (JPY￥4,000 for adults) and First-half period tickets (JPY￥5,000 for adults) will only be sold before the opening of the Expo.

https://ticket.expo2025.or.jp/en/faq/