Yes
Yes, and they are good for 1-year from date of purchase. From their website: General admission tickets are not date- or time-specific. Tickets are valid for one-time use and expire one year from the date of purchase. Tickets are non-refundable.
We did. Yes.
Yes, also online, pre-purchase.
Yes you can buy tickets prior to your visit
You should be able to it, I did it the week before.
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