Varenna -> Bellagio Ferry Ticket help please!

Hello! My family and I are visiting Lake Como on June 18. We want to avoid the possibly hour-long queues for the ferry tickets to take photos, so we would like to know if we can buy a ticket on the same day say, around 8AM to beat the lines, but use them later in the day, like around 11AM?

big thank you to all the lake como locals who help around the sub!