OP Challenge Improv Block

I've been enjoying the blocks that have been posted for the first day of Pat Sloan's OP Challenge virtual retreat. Naturally, with a lot of creative people involved, the original block is changing with each quilter who posts. In keeping with the technique of my quilt, I  improvisationally pieced one of the blocks for the back of my quilt. I'll take more pictures as the back starts to develop this weekend.