Oof. Uhh.. let's just say, 'a very long time'.
I try to update my webtoon monthly, and so far episodes have been about 25-35 panels long with this artstyle:
Needless to say, it's very labor-intensive. I'd be scared to find out exactly how many hours it takes to complete each episode.. and see just how much of my life this project consumes.
Between work, school, my (albeit sparse) social life, and my other hobbies, I also don't have a ton of time to devote to it. I'm sure I could speed up my process significantly if I decided to prioritize my comic over all else, gave up my other personal/professional commitments, sat down, and did nothing but draw. Or if I simplified my art style- or maybe found a partner to help me produce it. However, I don't feel I can (or want to) do any of these things at the moment.
So, for now, my story crawls along. :']