Approval Profiles determine the approval settings for each absence reason. Multiple Approval Profiles can be created in order to set separate approval requirements for different dates. A common use of this feature is to set days before and/or after a holiday to require additional steps of approval for specific absence reasons to allow for additional oversight.
The Default Approvals Profile determines the approval settings for all dates within a calendar year unless an additional approval profile is created.
Navigate to Organization > Configuration > Approvals
When additional approval profiles are created, the Default Approvals Profile will determine the approval settings for all dates except those that are specified in the additional approval profiles.