Floor 1056

After being shot through the chest, Bill Potts was taken to Floor 1056 of the Mondasian Colony Ship to be "repaired".

It was the lowest floor on the ship and thus the furthest away from the Black hole that the ship was slowly moving away from. As a result, time on this floor moved at a normal rate compared to Floor 0, where time moved so slowly that it appeared to those on Floor 1056 that there was no movement at all; 10 minutes at the top equated to years for those on floor 1056. (TV: World Enough and Time)

History
After 20 members of the initial crew on the ship went down to reverse the thrusters away from the black hole, the time differential caused the residents to age so fast that many generations have changed during only two days that passed at the top of the ship. A hospital was setup at some point, where the residents all inevitably went to be converted to preserve their lifespan. joined the residents at some point, acting as a the hospital's caretaker under the guise of "Razor". After an attempt to send a group to Floor 507 proved unsuccessful, "Project Exodus" was created, a plan to convert everyone into cybernetic humanoids so they could survive the journey upstairs. The prototypes would go to the upper levels to collect any remaining humans to take downstairs and eventually convert them. (TV: World Enough and Time)

Behind the scenes

 * The numbers of the floor equate to 12 when added together, a reference to the Twelfth Doctor.