Hi Adam,
Thanks so much for your interest in our plugins! While new plugin purchases with us include 12 months of plugin updates and premium support by default and will expire 1 year from the original purchase date, expired licenses can still be used on activated sites (except for Event Aggregator), and you can add additional site activations to an expired license, as well. However, it’s worth noting that you aren’t strictly limited to a single year of full functionality! You can renew your licensing with us at any time before or after a plugin has expired to gain an additional year of updates and support. You can read more about license renewals for our plugins on our Knowledgebase here.
I hope that helps! Thanks again, and let me know if you should have any other questions! 🙂