Since launch, players have been able to change their Switch system clock to jump forward in time and access events before they went live. Version 1.1.1, released June 18, closes that loophole.

The game now checks the server before unlocking any time-gated event content. If the server says the event hasn't started yet, you're not getting in.

This applies right away for the Jirachi visit, which starts June 23. You'll need to be online and on the real date to participate.