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In case of SLA metric being paused ("On Hold"), the actual deadline is unknown at the moment because it is moving forward (as the time on hold is not included in the Time spent). This is what could be called "flowing deadline".
By default, the issues where the SLA metric is On hold are not included in the search results of slaMetricDeadline("", "", "") function. It works this way because ignoreFlowingDeadline flag is set as 'True' by default.
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