When a new date and time is entered in Time Tracker, the Career Consultant (CC) that is currently logged in will forever be associated with that entry. Other data in the Time Tracker section (Type of Billing, # Clients, Interpreting) can be changed and saved by other users, but the name associated with the original time will not be changed.
For Activities, the CC that originally adds the activity will be forever associated with that activity. All activity data can be changed after it was originally added, but the original CC's name will never be changed even when a different user saves Activity data.
If you must change the original author of times and activities, you will have to be an administrator that uses the impersonate feature.