Introduction
Open Skype for Business on Mac. In Preferences > General, ensure that the box next to "Update my status based on my calendar information" is checked.
Instructions
1) Click the Skype for Business menu option, and then click Preferences.
2) Under the General tab, ensure that "Update my status based on my calendar information" is checked.
Outcome
Your Skype for Business presence will now be synced with your Outlook calendar.