Keep trying. Mostly I got "Sold Out", but a few times I refreshed and it said "Buy". By the time I'd worked out what blocked the ticket(s) were in, they'd gone. Then a block of ten came up - I could see them disappearing as I looked.
Gah, I so wish you hadn't posted that :-(
Just spotted it myself, thought I was going to be lucky...
To everyone else - go and do the gardening, or something else. Please.