When using eksctl 0.54.0 to update a managed node group from 1.19 to 1.20, the --wait=false flag still causes the command to wait for CloudFormation.
When using the --timeout flag that will make it only wait for the time specified, but the exit code is 1, causing it to fail any scripts I use the command in.
This is the command I used:
eksctl upgrade nodegroup --cluster cluster-name --name=nodegroup-name --wait=false --kubernetes-version=1.20