Sounds like you guys have made positive progress. I totally understand her being nippy as Chickie seems to be in a similar stage. She is much more willing to attempt a nip or bite than she was 2 weeks ago. I attribute it to her coming into her own and realizing that she might have a different opinion about things than I do. There are different schools of thought on this, but when Chickie becomes nippy or rude I sternly tell her "no" or "no bite" and then give her a second chance. If she continues the behavior then she goes in her cage for 10-15 min. After that I go get her and start fresh. Also, we have found that her behavior is very linked to how high she is. Her tree puts her at eye level with us and sometimes when she's being "bratty," as I call it, all it takes to straighten her out is to simply move her lower in her tree. She climbs back up to the top, but the act of us lowering her even only a few inches causes a 180 attitude adjustment. Hopefully others that are more experienced than me will have some good advice too, but it seems that our girls are quite similar so hopefully I've helped some.