Automated release notes being an app for Jira, needs to be purchased from Atlassian Marketplace. Automated release notes Cloud version can be purchased on monthly subscription as well as annual subscription. Below are the steps involved in completing the purchase.
For Monthly subscription, once your Jira admin installs Automated release notes Cloud version on your Jira instance, first month (30 days) of the subscription is free. Post that, you will be charged on monthly basis depending on your Jira tier.
Jira site administrators need to request a quote from this Atlassian link - https://support.atlassian.com/contact/#/. By using this link, complete the form, select highlighted options as shown in the image below. Add other relevant details and submit your request.
Atlassian team generates a quote for you. Automated release notes license key will be provided after successful payment for an annual subscription from Atlassian team.