Alternate Timelines

Alternate timelines are the result of changes in the space-time continuum, created usually via time traveller.

Rules
People and entities that are subjected to this changes will not remember their previous lives after the transition from the old reality to the new. However, those who are responsible for the change, can in some cases remember the previous timeline, as it was the case with Castiel, Balthazar and Atropos.

Changing the timeline can sometimes create temporal paradoxes, where beings and objects from a previous timeline can still paradoxically exist in the new one for a short period of time. An example of this was when John was transported from 2003 to 2019, Sam and Dean continued to exist as themselves, despite their lives also being affected and Mary Winchester was still alive, despite the events leading up to her resurrection never happening. However Sam theorized that this won’t last long and that Mary will just fade away, while he and Dean will become this new timeline’s version of themselves.

Alternate Timelines so far
My Heart Will Go On : an alternate timeline that came about when Balthazar prevented the Titanic from sinking on its maiden voyage, on orders of Castiel who needed more souls for his war against Raphael. Ellen and Jo are alive, Sam and Dean drive a first generation Ford Mustang and thousands of people who previously didn’t exist are alive and walking. This timeline was erased by Balthazar on Castiel’s orders.

Family Feud : an alternate timeline which was created when Abaddon kidnapped Gavin MacLeod, thus preventing him from sailing with The Star  and drowning in 1723. As a result, he was not present when his fiancé Fiona Duncan came looking for him. Fiona was brutalized by the members of the ship and became a vengeful spirit that murdered several teachers centuries later. This timeline was erased when Gavin returned back to the past.

Lebanon : an alternate timeline where John Winchester disappears in 2003 and is transported to 2019 as a result of Dean using the Baozhu. As a consequence, Mary stayed death, Dean continued to be a hunter and Sam became a successful corporate lawyer. Castiel and Zachariah remained in Heaven’s service and the Apocalypse never happened. This timeline was erased when John decided it’s best to return back to his time.