A particular Uproc does not perform one of the Completion Instructions (6) as seen below:
In the History Trace, we can see that the uproc in Yellow is not purged by the Completion Instructions as expected (only 5 out of the 6 Job Events are purged):
Release : 6.x
Component : DOLLAR UNIVERSE
Potential corruption of the Uproc definition
Recreating both the uproc/s where the Completion Instructions were not working as expected fixed the problem.