Weiss and Blake's capture by the mice is a homage to Gulliver's Travels.
Originally, the ninth volume was intended to have more episodes. However, due to reasons involving the COVID-19 pandemic and the animation department's scheduling conflicts with Justice League x RWBY: Superheroes and Huntsman Part One (2023), it was shortened to twelve episodes as the volume was rushed into completion.
The fact Weiss notices Blake trying to hold hands with Yang, but is too nervous, shows that she already knew about the two's attraction back in Volume 7. Explaining why she quickly joined Jaune and Oscar for a movie; she didn't want to a third wheel.