The specification is not clear whether the initial DataChangeNotification of a Triggering item is to be considered a trigger.

Assuming the following workflow:

1. CreateSubscription with PublishingEnabled = false
2. CreateMonitoredItems (1 MonitoredItem with MonitoringMode Reporting, several others with Sampling)
3. SetTriggering with a Trigger and the others as LinkedItems
4. SetPublishingMode to PublishingEnabled = true
5. Publish

In this scenario the UA Working Group in the meeting on 24th of June agreed, that the initial value for the trigger item is also triggering the publish of the LinkedItems. But there are major SDKs which behave differently so the group sees the need to describe the two use cases being possible with triggering by changing the order of the calls to ensure the same behavior between the products. The first option is what was outlined above the second option is to call publish after the creation of the MonitoredItems but before calling SetTriggering. In this case the initial value of the monitored item was already reported and the trigger would not occur.

Here is a text proposal for the specification to add a paragraph to 5.13.1.6 Triggering model:

The order of service calls when using the triggering model affects the behavior during initialization. Clients can choose between two approaches depending on whether initial values for the LinkedItems are required.

1. When initial values for LinkedItems are required:
   The Client shall call SetTriggering before sending a Publish request to the Server. In this case, the initial value of the triggering item has not yet been reported to the Client. When the Server subsequently receives the Publish request and generates a NotificationMessage, the triggering condition is met, and the current queues for both the triggering item and the LinkedItems shall be reported.
2. When initial values for LinkedItems are not required:
   The Client shall first call Publish after creating the MonitoredItems, and only then call SetTriggering. In this scenario, the initial value of the triggering item has already been reported. Since the links are created after the initial Publish, no triggering event occurs, and therefore the LinkedItems are not reported.