You can schedule on a non-work day (weekend or holiday) by clicking on the day and confirming.

​Allocations scheduled on a non-work day will appear over a red background with red diagonal lines on the Schedule. They are recorded as overtime hours in your reporting.
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​💡 Here's a tip: If you've set your account to hide non-work days in your Team settings, you will not be able to schedule on weekends. The Account Owner or one of the Admins can unhide the weekends to allow scheduling on these days.
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