Holiday schemas are used to plan when some group of employees will not be available. Each country may have different national holidays during which most employees will not be available. Like "Work Hour Schema" holiday schemas are used to calculate how much work log an employee should enter. At installation a Default Holiday Schema is created and it can't be deleted. Any user which who is not assigned a custom holiday schema is assumed to be a member of this Default Holiday Schema.
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From the add-on administration section click on "Holidays" link and existing holiday schemas including the default one will be listed. From this screen you can see which schemas exist, and number employee count of members of each schema. You can also add schemas, edit existing ones or delete a schema from this screen.
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