add cal file docs

action_setup.adoc

@@ -189,7 +189,7 @@ actioms:
 
 You will often want an easy way to schedule actions from the web interface as well, you can do this by creating a separate schedule action that adds an instant to the calendar file.
 
-You can use an action with a datetime argument to update the calendar file. You will have to adjust the hardcoded timezone to suit your needs, you can see below that "+00:00" is being added to "{{ when }}" to create an instant in the UTC timezone.
+You can use an argument with `type: datetime` to create a date selector in the web interface, to easily select dates to be added to the calendar file. You will have to add  hardcoded timezone to suit your needs, you can see below that "+00:00" is being added to "{{ when }}" to create an instant in the UTC timezone.
 
 [source,yaml]
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