[ObsoleteAttribute("This property is deprecated in Revit 2018 and will be removed in the next version of Revit. We suggest you use the SubVersionNumber property instead.")]
public bool IsSubscriptionUpdate { get; }

<ObsoleteAttribute("This property is deprecated in Revit 2018 and will be removed in the next version of Revit. We suggest you use the SubVersionNumber property instead.")> _
Public ReadOnly Property IsSubscriptionUpdate As Boolean
	Get

[ObsoleteAttribute(L"This property is deprecated in Revit 2018 and will be removed in the next version of Revit. We suggest you use the SubVersionNumber property instead.")]
public:
property bool IsSubscriptionUpdate {
	bool get ();
}

Subscription update releases may have additional APIs and functionality not available in the standard customer releases. Add-ins written to support standard Revit releases should be compatible with subscription updates, but add-ins written specifically targeting new features in subscription updates would not be compatible with the standard releases.