There are some very odd things about the colors 
in some CCS cels.  

In her "Final Judgment" costume, she wears a hat 
with a yellow circle around a paler yellow dot.  
Except in one of my cels, the inner dot is 
pink.

I have two cels of Sakura in her "Prince" outfit 
from the famous "transfiguration" scene at the 
end of the "Sleeping Beauty" ep. where she 
captures Light and Dark.  In one, the brim of her 
floppy hat is pink, in the other, it's black.  In 
both, the pleats in her sleeve are pink.  But in 
the broadcast, they are dark blue.  (And 
there are lots of other subtle differences in 
color, shadows, etc.)

The only thing I can think of is that in some 
cases the studio made two (three? four??) sets of 
cels, used the ones they liked, and put all of 
them, used and unused, on the market.