1956A

1956A was an ABC timeline and a year in the 20th century. The altered timeline it belonged to was created when an elderly Biff Tannen traveled from 2015 to give his younger self from 1955 a sports almanac to make himself rich.

Differences

Note: The following section is considered non-canon or is disputed in canonicity.

Biff didn't graduate with the rest of his class, as he was expelled for trying to bribe Vice Principal Stanford S. Strickland the previous year.
Biff begins pranking Strickland, which gets worse as the years go on.

Non-canon or disputable information ends here.

For years in this timeline after 1955, see the Hell Valley timeline.

Note: The following section is considered non-canon or is disputed in canonicity.

Date unknown:
- While Vice Principal Strickland is giving his speech, Match, Skinhead, and 3-D climb above the stage, releasing a banner that reads "Life's a Beach. SEA You Next Year!", while dumping a bucket of water on Strickland's head.

Non-canon or disputable information ends here.

Hell Valley (also known as Biffhorrific 1985) timeline

Years
1955B · 1956A · 1970A · 1971A · 1972A · 1973A · 1979A · 1985A · 1986A · 2015C
Stories
Back to the Future II · "Clara's Story" · Biff to the Future