You set up your availability for a regular week in the Availabilities section. However, in real life, last-minute things come up. Let's say you need to attend a function this coming Thursday. eetoCal provides availability overrides to handle these situations.
As the name suggests, you are overriding your availability. In the "Availability Override," you select the dates for which you want to override the availability mentioned in your weekly schedule. For example, let's say that typically, on Thursdays and Fridays, you work from 9 to 5. However, on Dec 7 and 8, you would be working only from 2 PM to 4 PM. You can achieve this using the "Availability Override."
If your schedule changes a lot from week to week, check out Handling different schedules each week.
Here are the steps you should follow to add an Availability override:
Click on the Availabilities tab on the left-hand sidebar.
Click on the availability you want to override.
Look for the Availability Override option and click on Add.
Add the hours you are available.
Click on Submit.
Once the availability override is set, then for those specific days, the override takes precedence over the weekly availability.