Hi all,
Noticed this error a few months ago and purchased as I wanted to confirm that a pack of 12 would arrive rather than just 1 can. My order arrived today, so I can confirm the error is legitimate and you'll receive a pack of 12 for $2.60 ($2.34 S&S).
There is a minimum order of 3, so you will have to receive 36 cans minimum, but at less than 20c a can with S&S, it's a bargain. You will only be able to purchase a maximum of 6 (72 cans), and even if you try to make a subsequent order for more then you won't be able to checkout, so we can safely avoid the hoarders and resellers on this deal, unless they have multiple prime accounts.
No dates on the cans for expiry, but looking online these will last a few years at least. Testers have been critical of this and say it's not nice, but I personally don't mind it.
First person I've heard of receiving a single can. But message Amazon Customer service through their live chat and they'll issue a full refund quite easily, and I usually ask for a promo credit for the inconvenience - should be able to bag a $5 one :)