SimpleMessageListenerContainer still picks up a message after calling stop

Question

I have an AWS SQS Queue with no retry (MaxReceiveCount is set 1). I have setup a DeadLetter Queue for the same.

I am using spring-cloud-aws-messaging, below is my listener class

@Component
public class MyListener implements ProcessingFinaliser {

    private final String sourceQueue;
    private final MyProcessor myProcessor;
    private SimpleMessageListenerContainer simpleMessageListenerContainer;

    public Mylistener(@Value("${my.queue}") String sourceQueue, 
                        MyProcessor myProcessor,
                        SimpleMessageListenerContainer simpleMessageListenerContainer) {
        this.sourceQueue = sourceQueue;
        this.myProcessor = myProcessor;
        this.simpleMessageListenerContainer = simpleMessageListenerContainer;
    }

    @SqsListener("${my.queue}")
    public void doWork(String message) throws MyCustomException {
        this.processor.processMessage(messge);
    }

    // Called when shutdown signal is called
    @Override
    public void finaliseProcessing() {
        simpleMessageListenerContainer.stop(sourceQueue);       
    }

}

SimpleMessageListenerContainerFactory#waitTimeOut is set to 20 seconds simpleMessageListenerContainerFactory.setWaitTimeOut(20);

The problem I am facing is that when simpleMessageListenerContainer.stop(sourceQueue) the doWork method still picks up a new message and goes to DeadLetter Queue as the container dies. Looks like the underlying PollingThread in SimpleMessageListenerContainer does not stop straight away.

By default the SimpleMessageContainerListener#queueStopTimeout is set to 10 seconds, would setting this to 0 be the right thing to do?

Can someone explain please?