Alternate timeline (The Crash of the UK-201)
From Tardis Wiki, the free Doctor Who reference
An alternate timeline was created by Vicki Pallister where she prevented the UK-201 from crashing. She wrote several stories about her travels with the First Doctor, which she still remembered from the original timeline. They were Vicki and the Crusaders (TV: The Crusade) Vicki and the Zarbi, (TV: The Web Planet) and Vicki and the Space Museum. (TV: The Space Museum) She also wrote one about the time she and Steven first met. (TV: The Chase)
