Cels Forum

When a cel is first being drawn out on paper, the animators
hang them in different positions on the peg-bar depending upon what 
it is they are animating.  Most production cels are hung from the top.
Some cels are hung from the bottom for the purpose that when they are on paper,
they can be flipped by the animator to view the motion.  Some are even hung 
from the side.    
I doubt that it is fan made.  If there is a sequence #, it's
more than likely a production cel.  If it's a reproduction, there
shouldn't be a number...and if there was, it could be considered
crossing the line into counterfiet.  It might also be that the cel
is just upside down. =P

Hope this helps! ^_^

gogeta00