>>4348886>This has got to be a rrat.It matches A-chan's claimed age (recently turned twenty, celebrated with a beer-drinking stream) and the start of Hololife/Sora's debut.
Whether A-chan's actual age matches her claimed age is a different question, but the manager maintaining kayfabe would be a bit weird, desu.
Obviously, she wouldn't have been Super-Manager-san straight away. She said what she did. She approached Cover to loan the tech, she got it, and landed Sora a gig as Cover's tech demo while she was at it.
After that, Sora's tech support, while Cover started to lean more heavily into the Idol aspect.
A-chan's idea, Cover took it up, and A-chan presumably stayed involved with Sora, then her responsibilities slowly expanded since Hololive was expanding beyond Sora, too, and she had the most experience.