Our process is similar to your a little. We just have a test and a production project for our various department.
If I remember correctly you can't move a workbook over top of one that already exits in a project.
I typically will down load the test workbook and then publish over top of the one in production. This keeps everything in place with subscriptions, views and refreshes. It also allows you to role back to a prior version if needed. Don't believe moving a workbook does allow for that.
Right now it is manual, but my volume is relatively low. I'd like to automate this using tabcmd to download workbook from test, publish workbook to production and then remove the test workbook.