I read on one of the references found on this forum about some of the puppy stages. It sounds like she is in the middle of testing her independence with you and forgetting her training. Ellie is starting to "forget" everything we've worked so hard on, and reading that really helped to know what is going on. Anyway, if you go into the Caring for your Cavalier part of the library, it is under Training your dog; puppy issues. Hope it helps!
*Kim, Teddy (10 month old Ruby boy), and Ellie (4 month old blenheim girl)*