I changed this website’s domain from graukaue.eu to graukaue.ruhr and hence this subdomain from en.graukaue.eu to en.graukaue.ruhr. The new email addresses are email@example.com, firstname.lastname@example.org, email@example.com, firstname.lastname@example.org and email@example.com. The URLs of the pages, posts, episodes and feeds have changed accordingly.
The addresses with the top-level domain (TLD) .eu still work, though. They are all being redirected so that you don’t have to take any action.