I think you do that job first until your online income is 3 to 5 times your salary because it quite stable right.
3-5 times? I think you will never get out.....1 to 2 times should be ok, the essential part is that the income should be stable.
I've never worked in my life, becuase what I do is "fun" not work. Quit your job if you have enough passion to put time and effort to making money online.
make sure that you are set for at least 3-4 months in the future in case something happens... you never know
What methods are you using to earn with your online business? I could definitely recomend some additional methods of monetizing your sites and boosting the online income you're earning. I'm guessing you've already quit and hope everything's going well. Are you working with affiliate programs? You can replace your old income by developing multiple income streams and with the great advice here, it's definitely possible to make your dream workable and make a decent income online (wherever you might be located). Best of luck to you and take care! (Feel free to ask for additional advice and/or support...)