My viewing distance is 20 chunks. The area might have contained a lot of air. The command block is at 29 249 -400.
/clone ~-1 ~ ~-1 ~+1 ~-31 ~+1 ~-10 ~-4 ~-11
returns
[12:10:30] Cannot access blocks outside of the world
but this isn't outside of the world nor is it in an unloaded chunk like in MC-32522.
Cannot confirm in 15w47a. Can tell at which coordinate you execute this command. If the Y value is too small that would be intended.