Convox’s certificate update path directly changed the load balancer’s certificate, started deleting the old certificate, and updated the CloudFormation stack. That gave two actors responsibility for moving the same listener between states.
My proposal removed the direct listener mutation and its retry loop. CloudFormation would perform the transition described by the updated stack.
The old certificate also had to remain. UpdateStack accepted an update; it did not wait for the entire operation to finish successfully. Deleting the previous certificate immediately could remove a resource CloudFormation needed if it rolled the stack back.
The final submitted patch left a comment explaining why that certificate would be orphaned for the time being. Cleanup still mattered, but it needed evidence that the resource was no longer part of a possible rollback. An asynchronous delete launched beside the update did not provide that evidence.
The PR closed without merging.