CMJ Integrity Check reports Duplicate object error Issue link type 'Epic-Story Link'
Symptoms:
Integrity Check reports: Duplicate object  Issue Link Type Epic-Story Link has duplicates
Cause:
CMJ requires that there are no duplicates when snapshot is created.
This behavior is provoked by known issue which results in duplicate Epic-Story Link entries in the DB. The cause for this is still being investigated by Atlassian.
Resolution:
Follow this Atlassian KB article https://confluence.atlassian.com/jirakb/duplicate-epic-story-link-types-in-issuelinktype-table-causing-errors-in-search-using-has-epic-779158623.html