Hi Melinda,
The swap is for a set of six. If you send one set you get one set back. You can send up to 4 sets. As far as you fabric is concerned, I suppose it would depend on what you make with it, for it to be qualified as a "summertime" block. LOL!
Let me know if you will be joining us. It is always fun to see what people make to swap with each other.