Just want to say... for fuck's sake. Another series in the shadowhunter world. I thought three (four if you consider the second trilogy in TMI separate) was enough. Now TDI is going to be a prequel to a prequel to a prequel, this series is going to be a prequel to a prequel, and TMI is going to be a prequel sorta thing to the Dark Artifices. Really? I think CC has lathered her skin in this shadowhunter business enough already, even with TDA unwritten yet. 
 Sure, Cassie can write as much as she wants and whatever she wants, be it in the world or something totally different. But I think after a while you construct this perception of an author and whether their ability to build new worlds and create new characters is really diminishing because you never see it happening, never see them writing something completely different. Sure, Cassie is writing for her fans. Sure, if it's making her and Simon & Schuster money there's no stopping this moving bullet train. The more we see this same world, however, the more it gets tiring. 
 Setting the many series in different time periods is perhaps a positive as it exercises one's ability to alter a world and introduce new characters and show the lineage of the original characters. There is also new stories and developments such as the automatons in The Infernal Devices. But what are we going to see The Dark Artifices as it's set in LA 2012, and in this 'TLH' series, set in 1903 after TID. The same thing over and over again? I hope not. How much originality can you infuse into a world you've already built and shown to your readers? If it's done right - like in The Infernal Devices - then there's no worries. However, if not, then the readership of an author such as Cassie Clare will decrease as a majority of readers will tire out and read other books despite how much they love the world. 
 We'll see by the time it comes around to the time of this release if I feel like reading these books after the end of TMI and possibly the end of TDA. We'll see. 
 (Then you have Magnus Bane Chronicles and that Shadowhunter Codex book.)