They do look like pure CCL. I'm wondering if maybe B isn't laying yet. I know you said she's over a year but maybe she's a very late bloomer. Here's an article to determine if she is...
https://www.backyardchickens.com/articles/who-is-laying-and-who-is-not-butt-check.73309/
https://www.backyardchickens.com/articles/who-is-laying-and-who-is-not-butt-check.73309/