Delete orgUnit referenced by a subprogram.
Then you get an exception :
java.lang.ClassCastException: org.ametys.odf.program.SubProgram cannot be cast to org.ametys.odf.program.Program
at org.ametys.odf.observation.UpdateReferenceOnOrgUnitDeletionObserver.removeReferencesFromAbstractPrograms(UpdateReferenceOnOrgUnitDeletionObserver.java:124)
And referrencedOrgUnit are not updated.