Last tested: Jul 18, 2018
Local project import should pull from whatever mode you're in. So, if you're in dev mode, it'll pull from the dev version of the code. And when you're in prod, it'll pull from prod.
If you want to always pull from prod, or from a static version, use Remote Project Import instead.
Note: If you lack model permissions to a project, then we create a clone of production for you to use while you're in dev mode. This can get out of date! In this case, it is recommended to use Remote Project Import instead. (Though it does not keep you up to date, at least you can specify a SHA.)