Cancels a scheduled service software update for an Amazon OpenSearch Service domain. You can only perform this operation before the <code>AutomatedUpdateDate</code> and when the domain's <code>UpdateStatus</code> is <code>PENDING_UPDATE</code>. For more information, see <a href="https://docs.aws.amazon.com/opensearch-service/latest/developerguide/service-software.html">Service software updates in Amazon OpenSearch Service</a>.