I have used CT flannels for 6 quilts now and they have VERY little shrinkage. The last time I used some, I measured the blocks after the quilt was finished and washed. The entire quilt - finished size 62" square measured a little over 61" square after it was washed. So I lost less than inch on an entire quilt top.
And if you love the feel and softness of it before washing it only gets better.