@Test
  public void testConflationCreateUpdate() throws Exception {
    server1.invoke(putFromServer(KEY1, VALUE1));
    server1.invoke(putFromServer(KEY1, VALUE2));
    server1.invoke(putFromServer(LAST_KEY, LAST_VALUE));
    expectedNoEvents = 2;
    client1.invoke(checkNoEvents(expectedNoEvents));

  }
In this test do a create & then update on same key , the client should receive 2 calabcks.
geode-core/src/distributedTest/java/org/apache/geode/internal/cache/ha/HAConflationDistributedTest.java