Full changelists:
Notion 6
https://api.presonus.com/notion6/change_log.html
Notion 5
http://update.notionmusic.com/notion5/change_log.html
Notion 4
http://update.notionmusic.com/notion4/change_log.html
Notion 3
http://update.notionmusic.com/notion3/change_log.html
New feature blogs:
Notion 6.8.2
https://blog.presonus.com/index.php/2021/08/24/notion-6-8-2-now-available/
Notion 6.8.1
https://blog.presonus.com/index.php/2021/03/08/notion-6-8-1-now-available/
Notion 6.8
https://blog.presonus.com/index.php/2020/10/20/notion-6-8-now-available/
Notion 6.7
https://blog.presonus.com/index.php/2020/07/07/notion-6-7-now-available/
Notion 6.6
https://blog.presonus.com/index.php/2020/02/06/notion-6-6-release-notes/
Notion 6.5
http://blog.presonus.com/index.php/2019/01/15/notion-6-5-change-log/
Notion 6.4
http://blog.presonus.com/index.php/2018/05/22/notion-6-4s-new-features/
Notion 6.3
http://blog.presonus.com/index.php/2017/12/13/notion-6-3-new-features-fixes/
Notion 6.2
http://blog.presonus.com/index.php/2017/05/23/notion-ios-update-v-6-2-available-now/
Notion 6.1.1
http://blog.presonus.com/index.php/2017/02/21/notion-6-1-1-maintenance-update-available-now/
Notion 6.1
http://blog.presonus.com/index.php/2016/12/13/notion-6-1-released/
Notion 6
http://blog.presonus.com/index.php/notion-6-new-features/
Notion 5.1
http://blog.presonus.com/index.php/presonus-releases-notion-5-1-update/