I'd highly doubt Australian 'Ecstasy' would return a postive results for anything these days.
If the pill contained MDxx or (Meth)Amphets, you'd be looking at 2-5 days, on average 2 or 3 in a a urine test. If the pill contained cathinones, piperazines, etc, then you'd be fine.
I guess if you KNOW you have a test....the simple answer would be wait till the following week!