0 - AlwaysInAdvise

Tag is kept updated if the OPC UA Block Tag's AllowRead property is set to True and the OPC UA Subscription's Enable property is also set to True

1 - AdviseWhenLinked

Tag is only updated if the OPC UA Block Tag's AllowRead property and the OPC UA Subscription's Enable property are set to True, and this Tag is linked to an active object, such as a Display on a Screen or an Alarm enabled, among others. The Tag's link for this purpose can be performed in the following properties: Value, RawValue, Quality, and Bit00 to Bit31 of OPC UA Block Elements, and Quality and TimeStamp of OPC UA Block Tags (default)