For those of you who have asked, here are the instructions I got from Sheila that she got from Sharon:
You have to think of the churn dash as a 9-patch block - then break those components for the size you need for the size block
a 9" finished block - each unit would need to be 3.5" (unfinished) - so 3.5" HSTs, the 'bar' sections would be 2" strips stitched together and then sub-cut into 3.5" , and a 3.5" center.
a 12" finished block - each unit would need to be 4.5" (unfinished) - so 4.5" HSTs, the 'bar' sections would be 2.5" strips stitched together and then sub-cut into 4.5", and a 4.5" center.
I used the 4 1/2" units, simply because I have more 2 1/2" strips than any other size. I also have the GO! die for half square triangles that finishes at a little over 4 1/2", giving me a very nice square after I trim it. It doesn't take many of those 12 inch blocks to make a good sized quilt.
I hope you try this one and that you share!
Hugs and kisses,