This article describes how to force the execution of the retention mechanism, deleting the oldest Call Analytics data without waiting the default schedule (01:15 AM).
1) Ensure the retention period is set to the desired value.
2) To force the deletion of oldest data from DB:
3) To force the deletion of oldest older raw CDR files from disk:
If you are coping with a full (saturated) DB, the above procedure may not work if the remaining space is very low. If not working, you need to delete oldest data using the deletion SQL script described in this article.