Sometimes it can take a long time to spin up a VM. It would be nice if we could set a number-of-VMs threshold where retention time does not apply. For example, I could keep two of my "general" VMs running at all times so jobs start immediately under light load, and new VMs only start getting created under heavier load.

Looks like the logic is in main/java/com/microsoft/azure/AzureVMCloudRetensionStrategy.java ?