The latest cumulative patch for CA PPM v15.1 (22.214.171.124) has been released and is available from the support download centre on August 14, 2017.
Announcement: CA PPM 15.1 Cumulative Patch 7 (126.96.36.199) General Availability Announcement
Please be sure to read the 'SPECIAL INSTRUCTION' section mentioned in the README if applying the patch and intending to use OR already using Jaspersoft Reports and Data Warehouse.
Note: The latest cumulative patch information is now available in the CA PPM documentation. Find the patch highlights, a link to the patch announcement, the Readme, and a link to download the patch on the Release Information, CA PPM and Jaspersoft Patches page as mentioned in the screenshot
where can I find the release notes for CA PPM v15.1 (188.8.131.52)?
There is no release notes for patches.
The read me for path 184.108.40.206 is at
Release notes are for the main versions eg
Release Notes (On Premise) - CA PPM - 15.1 - CA Technologies Documentation