Thanks for the reply. I don't think the AWS modules you linked are what I need as we're just using AWS IOT Core like an ordinary MQTT Broker. What I was hoping was that I'd be able to have the Sparkplug messages publish to a topic structure that simply had a root prefix I could configure. E.g.
myTopicRoot/someOtherPart/spBv1.0/<Group ID>/<Message Type>/<Edge Node ID>[/<Device ID>]
Regards, John.