Can you not schedule a scrub ahead of time? Website says scrubs must be reserved but everyone says sign up when you get there. I was planning on going Saturday or Sunday and don't want to not be able to get one done.

It's better to schedule to be on the safe side.

Its based on availability and Weekends are busy. From fri to sun. I know you can do it on the spot.

You reserve in the men's bathing area there are 2 men who do the scrub. There will be no problem

When you get there you'll reserve a spot while you are spending time in the spa

Usually they don't need to schedule but they have no commitment to you if you did not schedule in advance. So if you are trying to make sure to get one, You definitely should call them ahead of time and schedule it.