How WooCommerce Renewals Work
For Digital / Downloadable products
When you have set a renewal price for a digital product, the plugin then syncs the renewal price with the Download Expiry field of WooCommerce. A Renew button will appear on My Account page when the digital product is about to expire. By default, Renew button will appear 31 days prior to the product expiry.
For Physical products
When you have set a renewal price for a physical product, then on the next purchase of the product, the renewal price will get applied on it & the customer will get the product at a discounted price. A Reorder button will appear next to the order.