We are following the same policy as Odoo does – we develop the new features only for the 3 latest Odoo versions. For example, if the current Odoo version is 17, then we develop new features ONLY for Odoo versions 15,16,17.
For the lower Odoo version we do only bug fixing for customers who have modules already. Plus, an additional requirement is to subscribe to our Ecosystem for the advanced features. Select your plan here https://ecosystem.ventor.tech/
Note that if you already purchased the module via Odoo app store less than 6 months ago, please, contact us through our support portal to receive a special promo code for 50% discount for Ecosystem subscription for the first year. In your message, please, mention SO number on the Odoo app store so we can check date of the purchase.