Apple Calendar allows you to mark individual events as Free or Busy, to control whether or not the event affects your availability. If an event in your calendar is marked as Free, then you will appear as available during that time slot online when someone books a meeting with you on WhenWorks.
To mark an event as Free:
- View the event in Apple Calendar on your iOS device
- Tap Edit
- Tap Show As > Free
Once an event is marked as Free, it will not affect your availability in WhenWorks.