This was not the novel/diary I was expecting, and I'm very happy that it wasn't. The author notes in her afterword that she was told by a friend, "Don't even try and copy Jane Austen. ... Just be yourself, be respectful, and know that whatever you do, she is sitting up there in author-heaven laughing at you." I don't believe for a moment that Austen is laughing. I think she's likely quite jealous!
Yes, Lydia at first comes across as the self-important young teen as we experience in Pride and Prejudice, but this telling has her evolving with every diary entry she writes. She demonstrates a level of caring we don't see in the original since hers is not the story that is being told, and here it is. She demonstrates herself as extremely enterprising, and Farrant gives her a backstory to explain her ultimate pairing with Wickham that no one would have expected. A marvellous read!