Document.RemoveDateAndTime (Word)

Sets or returns a Boolean indicating whether a document stores the date and time metadata for tracked changes.

True removes date and time stamp information from tracked changes. False does not remove date and time stamp information from tracked changes. Use the RemoveDateAndTime property in conjunction with the RemovePersonalInformation property to help remove personal information from the document properties.

ActiveDocument.RemovePersonalInformation = True 
ActiveDocument.RemoveDateAndTime = True