Sometimes the sellers get e-mailed an offer that 
they can't refuse, and end the auction early.  
That's not uncommon to happen.  I've done that 
several times before.

I was eyeing that cel too, and a stuck sketch 
wouldn't of made that big of a difference in 
price to me...That's a nice cel...It should have 
gone way higher than it did...But...Hey...You 
never know unless you ask the seller directly^^'!

Hope that little bit helps!