Slightly different issue -- I have scheduled searches that work correctly but occasionally they get rescheduled (run again). So, these are not duplicate alerts.
This is problematic for summary indexing searches which are writing duplicate events to summary when this happens.
Smells like Bug.
SPL-96851 Summary searches scheduled can rerun during SHC captain re-election process
From Splunk: Fixed in 6.3 and back ported to 6.2.4.
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