flush API not working as expected

I am trying to use the flush API to clear the dimension cache -

Cube MetricsCube = rcon.getSchema().lookupCube("Metrics USD", true);
SchemaReader schemaReader = MetricsCube.getSchemaReader(null).withLocus();
Member memberTimeJul22 = schemaReader.getMemberByUniqueName(Id.Segment.toList("Time", "2013","Jul2013"),true);
final CacheControl cacheControl = rcon.getCacheControl(null);
CacheControl.MemberSet regionTime = cacheControl.createMemberSet(memberTimeJul22, false);
cacheControl.flush(regionTime);

But this call does not seem to clear the dimension cache. I am still seeing the stale data in the saiku UI