This is what it says on the website:
✤ Valid for 30 days from the date selected for the visit on the calendar at the moment of the purchase
✤ Usable for 72 hours from the first passage
I was under the impression that if I buy tickets today for July 1, that the tickets would be valid for entry anytime between July 1 and July 30, but once I first use the ticket, it expires after 72 hours. However, according to the customer service rep from the official website, the tickets would only be valid for 30 days from the date of purchase. So if I want a ticket for July 1, I can only purchase 30 days in advance.
Has anyone experienced this, i.e. where they have purchased a ticket more than 30 days in advance and then found the ticket to be invalid when they arrive at the Duomo?