Hi Haney,
Welcome to the Heartland Owners Forum and hopefully to the family. We have a great bunch of people here with lots of information and all willing to share their knowledge if needed.
I, myself, have never heard of 12 pack dinette option. Could you tell us what unit your looking at so that maybe someone that has one can help us out here?
The only 12 pack I know of is the kind that goes in the ice chest or fridge.
Althou,,, my 9MM magazine holds 12,,, so that could be a 12 pack also.
Enjoy the forum.
Jim M