Likewise! I'm halfway through myself. I'm a huge HP fan, and the concept of a Harry Potter universe with slightly modified initial conditions taken to a logical conclusion ("taken to a logical conclusion" being the operative phrase with this book) was hugely appealing. Loving every page, would highly recommend.

Another fanfic that's well worth reading for the consumate HP fan, although cut from a very different cloth: Dumbledore's Army and the Year of Darkness [https://www.fanfiction.net/s/4315906/1/Dumbledore-s-Army-and...]. If you've ever read Ender's Game, imagine Ender's Shadow for Book 7 of Harry Potter. :)