Benihana 30$ birthday gift card!?

Wow, benihana is so awesome. As far as i understand, they have a deal that if you sign up for the "chef's kitchen" or something like that club online you get a free meal of a 30 dollar value on your birthday. I was wondering if anyone has used this before or knows if it has to be used the day of your birthday or can it be used within a few days of it? Thanks|||I bet you could find the answer if you went online to their website!