Thanks!
So you can import/export circle settings in JSON, but there's no built-in way to batch-create them, although it shouldn't be too hard to implement. I believe there is a way to do it with automated browser scripting, but I've never tried it, so you would be in uncharted waters. It's also possible to write some custom JS functions and run them from the inspector in chrome, but you'd have to reverse-engineer the code which technically goes against the license. But a custom license is always an option :)