If the official has not set their own availability or have requested for your to set their availability, you can do so from your League Login
Edit Official Availability
Navigate to Officials click Edit Availability under the Actions.
Set the Availability of the official
Add an Availability Override for their current listed availability.
Enter in any Blackout Dates for the official
Set any note for the official
Note: Officials can also set their own availability at officials.teamlinkt.com