You will still have some couple of interviews, before they ask you to buy ticket. Once you buy tickets your departure will be between 3 weeks to one month. If you are going for the next interview, go with your entire family, especially if you have kids, most times it makes the Cbsa officer feel some compassion, you might get administrative deferral, it has worked in some cases. One more thing ,After expressing your fears of going back home ,If you are asked , "if you will leave Canada when you are asked to leave?" just answer them , you will leave if the law say so.