Amazon MQ - support for setting stomp hbGracePeriodMultiplier

We are using Amazon MQ (Apache MQ), along with STOMP to deliver content to our customers. We wish to keep the connection alive using heartbeats and on the client are setting incoming to 10s and outgoing to 10s, however we occasionally see heartbeat timeouts, I believe due to servers strict enforcement of timeouts.

For our local Apach MQ test server we can avoid this problem by setting "hbGracePeriodMultiplier=1.5" like so:

<transportConnectors>
   <transportConnector name="stomp" uri="stomp://localhost:61613?transport.hbGracePeriodMultiplier=1.5"/>
</transportConnectors>

See Active MQ documentation for Heatbeats: https://activemq.apache.org/stomp However on AWS MQ configuration for transportConnector (https://docs.aws.amazon.com/amazon-mq/latest/developer-guide/permitted-attributes.html#transportConnector.attributes), there is no uri or relevant attribute listed.

Am I missing something - is anyone aware of a way to configure a heartbeat grace period on AWS MQ?