What's worse is the documentation straight up lies. It states you can perform a major version upgrade by resorting a snapshot and selecting a higher version. I mean it's still not ideal except if you do try this you'll find the option doesn't actually exist - either via the console or API/CLI!
https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide...
This has really put us off using other AWS managed products and was a major factor in us deciding against using Amazon Elasticsearch Service.