Ah OK, so to answer my own question (for others that may not be able to find it like I couldn’t!):
Using one license for your live and dev sites
User often ask, “if I have a staging/dev site and a live/production site, do I need two licenses?”
Nope, just the one will keep you covered! Having a license key on your site means that you get automatic updates on your site when we release a new version. It does not effect the functionality of the plugin.
You can have your license on your dev site during development and then move it when you are ready to go live. If you need updates on the dev site, you can always move the license again or do a manual update with a latest version from your account’s downloads page. If you need help, feel free to post in our support forums.
https://theeventscalendar.com/knowledgebase/using-one-license-for-your-live-and-dev-sites/