So my question is if I've uploaded a scenario to the club and then make changes to the scenario do I have to reupload it to the club again or will it change automatically for anyone that downloaded it?
Yes you have to press the reupload button, because CC needs to know that you've made changes. Otherwise the old version will remain. But it isn't necessary to fill up the info box again, which appears automatically after the reupload. After that, every subscriber automatically gets the latest version.
