Honestly, I don't know when the TYBW manga starts. But you could search manga databases or ask in manga enthusiast communities to get the details you need.
Well, in a good 'cour ean rwby fanfic', the writing style matters a great deal. It should be clear and descriptive so that the reader can easily picture the world of RWBY as described in the fanfic. Also, it should have a proper pacing. Not too slow that it bores the reader, and not too fast that important details are missed. And of course, it should respect the source material. If it goes against the basic concepts of RWBY like the nature of Dust or the purpose of the Huntsmen and Huntresses, it won't be as good.
The theme of secrecy is also very prevalent. Vampire la Cour members usually need to keep their existence a secret from the human world. This secrecy can lead to many plot twists, like when a human accidentally discovers their secret or when they have to cover up any mistakes that might expose them. It adds an element of suspense and danger to the stories.
The TYBW arc's starting chapter isn't a straightforward answer. It could be different based on the manga version and region. I suggest looking at dedicated manga websites or asking fellow manga enthusiasts for the exact chapter.
I'd suggest checking manga forums or dedicated Bleach fan sites. They often have detailed breakdowns and recommendations on where to pick up after a specific part. Sometimes, the author or official sources might provide cues as well.