I think you have a good plan. You want to make sure you take your creatine starting 3 days before to your UA daily. It will take time for your body to process it into creatinine which is what may be measured to check against dillution. Also why you would want to use gatorade instead of water the day of your UA. If you are using creatine now as part of your workouts, you should be in good shape. Lets us know how things workout.