When I originally bought the bird, around 6 months ago, the cere was about the same color (purplish brown). The budgie is definitely between 1-2 years of age right now. I have seen the cere change color from darker to lighter but that's about it.
I originally bought the bird thinking it was a female but I am having second thoughts now. I think it might be a male because when I paired the opaline with a cock the opaline was the one that was feeding the cock all the time. And when I observed them it was the opaline that was puting a leg on the other male.
Here's a picture 1 month after I got him/her (zoom in to get better look):
http://picasaweb.google.ca/homebredbirds/G...464203945303810