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Using buildLabel in the JBE vs BF Agent causes different behavior

When I use the buildLabel property from Jazz Build Engine it gets expanded to something like 20120922-1002. However if I use the buildLabel property from the Build Forge Agent engine it gets expanded out to something like 20120922-1002380868. This causes confusion if I am sharing some information using the build label as there are it would appear to be different build labels depending on the engine. What causes the problem with the buildLabel property?
Accepted answer

The JBE and BF Agent have different mechanisms for determining what the buildLabel property should be. There is a difference between the JBE and BFA which causes the buildLabels to be different. This behavior has been entered as a defect: Various build label problems with JBE and the integrations (238409)
In the meantime, consider using buildResultUUID which is consistent for the build result as a workaround.