Canceling a deployment in app director just marks it as failed and no new tasks in individual vms will be picked up for execution. One has to explicitly teardown the deployment if created VMs need to be destroyed.
The wait of one hour is intended to ensure at-least creation of VMs is completed, as this is the step that's typically not cancelable in a reliable fashion across various cloud providers.
We'd take the feedback for a new feature request - enable cancel on deployments right after VMs are provisioned - this way you only have to wait until VMs are provisioned which typically is lot less (~ few minutes) than an hour. Can you confirm this would address your issue?
Thanks Rags
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