maxConcurrency

The maximum number of targets this task can be run for, in parallel.

Although this element is listed as "Required: No", a value can be omitted only when you are registering or updating a targetless task You must provide a value in all other cases.

For maintenance window tasks without a target specified, you can't supply a value for this option. Instead, the system inserts a placeholder value of 1. This value doesn't affect the running of your task.