Employee last_modified_at is not touched by work schedule change

Hello,

while building an integration to the Personio API (combination from v1 and v2), we have noticed that changing the work schedule of an employee, does not trigger the "employment.update" webhook and it also does not update the "last_modified_at" value that is retrieved from the employee API on https://developer.personio.de/v1.0/reference/get_company-employees-employee-id . Is this intended behaviour and if so, is there an alternative endpoint that can tell us that the work schedule of an employee has been updated by a last_modified_at timestamp or a webhook that would be triggered by this change?

Thanks for your support