This comes as a feature request from one of our Enterprise users. If you want to leave a domain to expire but keep the content and move it to another blog, then Clone blog will make your life a lot easier.
Clone Blog
Go to the blog you want to copy the data to, or create a new blog. In the top right, click the three dots and select Copy data from blog.
Choose your blog from the dropdown.
This will wipe the existing blog and copy the data from your chosen blog. Give it a few minutes, keep an eye on the Activity log and it’ll be finished without any hassle.
Hope it helps and keep the feedback coming!