Last night I made an on-line "B-ticket" booking for the Accademia. But I erroneously booked a date when I will not be in Florence. My credit card has been charged. The B-ticket website claims that all on line bookings are final. No changes and No refunds. Page 470 of Rick Steven Italy 2017 suggests otherwise. Which is the correct policy for a B-ticket reservation? Thanks. richard
Email them and ask. I was able to get a booking changed for the Historic Green Vault in Dresden when I made a similar mistake, but it's never guaranteed.
I read that page as saying that tickets booked by phone are not paid until you pick them up, in which case you're not obligated to take and pay for all of them. But that's different from the process for the pre-paid online ticket. When you "bring your voucher to swap for an actual ticket," it will be for the reserved time. Try to clear this up now, since the time you actually want could sell out.
E-mail them. I don't want to give you false hope but I managed to reserve the wrong week for the Vatican! And didn't realize it until I arrived.
They were fortunately forgiving.