Depo shot, gastric byp, and the pill.. When can I get pregnant?

I was on the depo shot for a year. I got gastric byp 2 months ago and have lost over 50 lbs, thank you, lol. But because of the sudden weight loss, my period has been nonstop since the surgery. (I've never had break-through bleeding on the depo before). So I got switched to Notrel birth control to stop the bleeding. I'm trying to get pregnant soon. How long do you think it would take if I stopped taking the birth control pills?