The task list in a runbook is ordered by the planned start time, which takes into account when the last predecessor is expected to complete, in addition to any fixed start times. It works this way in planning and in run. Planned start time ordering, and what happens when multiple tasks have the same start time.

A summary of task ordering is as follows: Planned start time > Dependency > Creation date > Alphabetical order

The example below shows a simple runbook where tasks are ordered by planned start time.

Where we have multiple tasks that have the same planned start time, we then order these by dependency. When the dependencies are also equal, the tasks are ordered by created date and then alphabetically.

The example below shows a runbook where all of the tasks have the same planned start time and the same dependency.

In this scenario where the tasks have the same dependency, they are then ordered by the time they were created - in a descending order. The screenshot shows that task 6 was created last and this is at the top of the dependency block.

You can have a scenario where multiple tasks with the same dependency can all have the same created time. This can happen because of an import or they were created in bulk. In this scenario, tasks are then ordered alphabetically by name.