+Update Steps
+------------
+
+Each service template may optionally define a `update_tasks` key, which is a
+list of ansible tasks to be performed during the minor update process.
+
+Similar to the upgrade_tasks, we allow a series of steps for the per-service
+update sequence, but note update_task selects the steps via a conditional
+referencing the step variable e.g when: step == 2, which is different to the
+tags based approach used for upgrade_tasks (the two may be aligned in future).
+
+