I honestly think that one, they change massively in their first few months. Jagger used to make my ears bleed. Now Hendrix never shuts up and Jagger isn't very vocal at all. And two, when they first arrive with you they are in a period of rapid growth and I swear that influences how much they sleep. When mine reached about 9 months they weren't growing so quickly, it felt like all of a sudden they seemed to be awake more and causing more mischief than ever. Around that time Hendrix was always looking to steal my glasses off my face or pull clips out of my hair, every night like clock work at about 9pm. He was such a pest!
That may be the stage you've reached - and maybe her personality is developing more now she's fully settled and had her hormones dealt with. It is amazing how much they change and blossom as they grow and become fully comfortable with you (and how far they can push you!). Their vocal range develops too - Hendrix didn't make half the warbling and trilling noises Jagger used to make - but now he does them too, and he has a very woeful sound he makes too - usually he is just looking for attention though! He knows that noise makes me rush over to see if he is okay
She may just be practising her vocal range!!!