An event can be created by the Source/Editor at any time up to and including D. 

An event may have a maximum lifecycle span of between D-20 years to D+10 years. 

Contributors wishing to change or add data during the lifecycle prior to D, unless otherwise agreed, must coordinate with the Source/Editor.
All changes to the event including deletion (event archived) will be recorded by NET and summarised in a history of changes for each event. 

Notifications of changes to event data by Contributors will automatically be sent to the Source/Editor.

In addition, you can use the Subscription feature if you would like to receive notifications (provided in a summary e-mail each day) of changes to events.