When you create a Trial Event, it shows the 'hosting period' is active for 7 days. That means this Event will only be active and functional for that period of time. You will not be able to access the Event after the hosting period ends.
For a Premium Event, the hosting period is 1 year. Since the Event will be active for one year, you can create the Event, knowing you have plenty of time to print invitations, including the LiveShare QR code. You can use the Event at your Wedding Shower, at the rehearsal and rehearsal dinner, Wedding, Wedding reception, honeymoon, etc. And your guests will have plenty of time to download photos after your event as well.