The availability feature is completely private to you and is purely for your own use, meaning customers will not be aware of the dates you have blocked out or your standard working days/hours.
This feature is purely to help you filter out requests that you already know you'd be unavailable for and will help you reduce/refine the requests we send you.
To update your availability:
Open the main menu and select Request Preferences
Click on Availability
Select your working days or choose specific days to block out in the calendar when you're already booked