PersistencePackageRequest ppr = getSectionPersistencePackageRequest(mainClassName, sectionCrumbs, pathVars);
Entity entity = service.getRecord(ppr, id, mainMetadata, false).getDynamicResultSet().getRecords()[0];
// First, we must remove the collection entity
PersistenceResponse persistenceResponse = service.removeSubCollectionEntity(mainMetadata, collectionProperty, entity, collectionItemId, priorKey, sectionCrumbs);
// Next, we must get the new list grid that represents this collection
ListGrid listGrid = getCollectionListGrid(mainMetadata, entity, collectionProperty, null, sectionKey, persistenceResponse, sectionCrumbs);
model.addAttribute("listGrid", listGrid);