We have a cover! Excited to be part of this. The publisher site for the book is https://www.routledge.com/Bayesian-Workflow/Gelman-Vehtari-McElreath-Simpson-Margossian-Yao-Kennedy-Gabry-Burkner-Modrak-Barajas/p/book/9780367490140

Note that a PDF will be freely downloadable once the book is out!