Stitchingpost
You can send all the same fabric, different fabrics, the choice is yours. If you want a purple & yellow quilt you can alternate and send half the group one color and half the group the other. You can ask them to please use a white background for their block if you wish but you cannot ask for a specific block as the idea to this swap is for people to stretch and grow and try new things.
It would have a mailing deadline of somewhere between the end of November and mid-December based on when signups close.
You can make the same block for everyone if you wish or you can make everyone something different or you can make the same block for half and a different one for the other half-again all up to you your choice. This is designed to help members stretch their skills, learn new techniques & work in colors they may not have necessarily chosen to use because it is outside of their comfort zone.
Hope this helps and if you have any other questions, I am here to help.
Hugs
April