For better or worse, my organization has projects (repos) with spaces in their names. When I attempt to push, these fail with a 404. The mp status output looks like:
Test Project planned (push error) GET https://gitlab.example.com/api/v4/projects/foo/Test Project: 404 {message: 404 Project Not Found}
I suspect a URL is being improperly generated without escaping special characters. I can't tell if this is a microplane issue or an issue with the gitlab library.