Something I'm confused about

[Cali&Pilot]

So when I got pilot back in Febuary I think it was, her Cere was brown which is how I knew she was a female, and over time her Cere has changed to a light blue and white, which indicates a young female budgie, and I'm kinda confused about that, and I don't really understand what that could mean, I haven't really dug to find anything out but if you guys know, could you please tell me why that might have occurred?
She is overall doing well but is bonding with me more than shes playing with her toys, I try to let her out every day, and she likes to preen my shoulder and my face, she has discovered that she can watch my phone, and I have a bird game on my phone that the background noise is like a rainforest and she will sit on my chest and watch me play the game. She is a good bird and I love her a lot, I personally think our bonding is going well and I have even taught her to jump from my shoulder into her cage at night when its time for bed, she used her cuttle bone for the first time the other day, its stand broke and it fell off her cage wall and she decided to use it and never used it before, I got her a forraging box but she hasn't used it and seems afraid of it and I am not sure how to introduce her to it. I know I got off track but I'm confused about the Cere thing

 

[DonnaBudgie]

It sounds like she's doing great! Not all birds play with toys, especially if they're interested in their human like Pilot is. Some budgies love to destroy cuttlebones and some just scrape them every now and then.

A female budgie in breeding condition will have a tan-deep brown cere, and when not in breeding condition the cere will be whitish pale blue. She may go in and out of breeding condition throughout the year with her cere changing color or her cere may just stay a shade of tan-brown. She sounds normal and quite happy to be your friend. She will do fine without a budgie friend as long as you give her attention every day. Male budgies seem to need budgie friends more than females, who are more independent. My female budgies mostly ignore each other and often ignore the males unless they're pair bonded to one.