Best Buy Pre-Employment drug test

Tomorrow (Friday) I will be going in for my final interview for Best Buy at 4:30 at which I will probably be offered employment and told to take a drug test. I've heard that they either give 24 or 48 hours to take the test at a clinic. Does this mean business days and that I can take the test on Monday or are weekends also included in the time constraint. The clinic is closed on weekends so I would be forced to take the test tomorrow in that case.

Also...I'm following N2's dilution tips to a T and I'm wondering how much creatine I should be taking each day on the days prior to the test, would 2x the daily dose be enough? I'm only 5'2" and 106 lbs.

Thanks!