Your availability status tells your collegues if you are currently available or not in case they want to contact you. It also shows them when you'll be available again. When your status is Unavailable, your won't receive any push notifications on your mobile device or desktop.
Please note that availability status doesn't affect your online/offline status.
You can check a person's availability status by hovering over their user icon anywhere in Space:
To see your own current status, look at your status icon on the quick actions menu. Click it to see the details and to change your status:
Your availability status is affected by the following:
Notification hours. You can specify when you want to receive push notifications for each day of the week. If you haven't set your notification hours, you will receive notifications from 8:00 to 20:00 including weekends. Your availability status will change according to the selected schedule.
Absences. When you report an absence, you specify whether you'll be available or not during the absence. When the absence takes place, the status specified in the absence will override the status set by notification hours.
When you change your status manually (from your user icon on the quick actions menu) you override all the setting above.