Integrations
It is already possible to publish release notes automatically on Confluence (follow this guide). There are other use cases where the release notes should be integrated with a few other tools that your team uses.
Some ideas are shared in this article.
Saving PDF release notes to Box
If your team is using Box for document storage, you may want to store the PDF release notes directly to a Box folder. This is very easy to set up via ARN. You just need an email address corresponding to the relevant Box folder. Once this email address is configured within the ARN email action, any attachments to the emails received on that address will be automatically saved to the folder.
Follow these steps - https://community.box.com/t5/Upload-and-Download-Files-and/Upload-to-Box-Through-Email/ta-p/50552
Saving PDF release notes to Dropbox
Similar to Box, there may be a need to store PDF release notes in a dropbox folder. While dropbox does not offer an email address directly for a folder, it is easy to set up a zapier integration.
Follow these steps - https://zapier.com/learn/how-to/email-to-dropbox/
Saving PDF release notes to cloud storage
Similar to Box & Dropbox use cases explained above, possibilities to store PDF release notes to Google drive, One drive & other cloud storage providers exist.
You can easily achieve this by using tools such as Zapier or Integromat.