I wonder how many of the Stars can live off the Holo job. Seems like it's not enough for Regis, or he may just have picked up some work while he is on mostly-hiatus.
(a)
I know several Nijis do regular jobs on the side, and I guess VTubing as a whole lends itself to being a side hustle since most indies do it for little to no pay at all.
Unless you're at the tippy top of the VTubing sphere, doing events and promotions all the time, you're probably going to have enough time to fit in a flexible part time job.
Altare mentioned during Wilds that he picked up a part-time job during hiatus to get himself out of the house IIRC. Gook boy's also been a depressive fuck prior to Stars. According to him, he also won't be in anything prior to April.