Probably not helpful, but I joined my first band in my early teens, albeit on guitar. We were mostly fairly bad, so it didn’t matter. Because I had already many years of playing in bands on guitar, when I switched to bass it was with the intention of joining a band in pretty short order. I don’t remember how soon it was after jumping ship, but I’m going to guess at 3-12 months.
One of the reasons I moved to bass was to get more gigs, I think it was 2000 (I’d previously moved to bass in the early ‘80s, but I was asked to join a band on guitar and went down that rabbit hole again for a good while).
Try going to some open mic events, once you’re comfortable jamming with others, you’re ready for a band.