Provided Updated Text to eric in the form of an e-mail also included here (but loose formating here)

Historical Audit Events

AuditEvents are generated as a result of an action taken on the server by a client of the server. For example, in response to a client issuing a write to a Variable, the server would generate an AuditEvent describing the Variable as the source and the user and client session as the initiators of the Event.
Servers must generate events of the AuditHistoryUpdateEventType or a sub-type of this type for all invocations of the HistoryUpdate service on any HistoricalNode. See [UA Part 3] and [UA Part 5] for details on the AuditHistoryUpdateEventType model and its sub models. In the case where the HistoryUpdate service is invoked to insert HistoricalEvents, the AuditHistoryEventUpdateEvent must include the EventId of the inserted event and a description that indicates that the event was inserted. In the case where the HistoryUpdate service is invoked to delete records, the AuditHistoryDeleteEventType or one of its sub-types must be generated. In particular a DELETERAW or DELETEMODIFIED must generate an AuditHistoryRawModifyDeleteEventType event or a sub-type of it, A DELETEATTIME must generate an AuditHistoryAtTimeDeleteEventType event or a sub-type of it, A DELETEEVENT must generate an AuditHistoryEventDeleteEventType event or a sub-type of it. All other updates must follow the guidelines provided in the AuditHistoryUpdateEventType Model.

Added text supplied by Paul H.

OPC UA Part 11 - Historical Access RC 1.01.07

Discussed in Telcon Aug 31st