There are some conditions under which the silkscreen on the back of the case appears on the front in error. This will not affect your order! These are the conditions under which it is known to occur:
Silkscreen the front and back of a box
edit the front
remove the silkscreen
import the silkscreen back
save the face
now the back silkscreen appears on the front. to fix this:
Edit the front face again. (the correct silkscreen should appear)