When a Build contains a manual stage, the build duration is not calculated correctly.
This is reproducible on Data Center:
in the above scenario the queue time are considered negligible.
The build should have the previous build duration + 10 minutes
The build the build duration is much higher.
Currently there is no known workaround for this behavior.
It ha been opened a bug https://jira.atlassian.com/browse/BAM-21817
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