When unsubscribing from your Instant subscription, any layouts that exceed the limits of the free plan must be unpublished. You’ll be prompted to do this during the unsubscribe flow within Instant.
If you unsubscribe by removing the Instant app from your Shopify store, your pages will remain active, but a 'Built with Instant' badge will appear in the bottom-left corner of the screen as part of the free plan experience.