criteria.addFilterCategory(COVERAGE);
criteria.addFilterVersion("0");
// One of the next two filters will be null
criteria.addFilterDriftDefinitionId(request.getDriftDefinitionId());
criteria.addFilterId(request.getTemplateChangeSetId());
criteria.fetchDrifts(true);
criteria.setPageControl(PageControl.getUnlimitedInstance());//disable paging as the code assumes all the results will be returned.
PageList<? extends DriftChangeSet<?>> changeSets = findDriftChangeSetsByCriteria(subject, criteria);
if (changeSets.isEmpty()) {
return null;