Currently, the "Create final attendance records" only creates AttendanceRecords if none exist. If the button is clicked before all RawAttendanceRecords have been uploaded, then incorrect AttendanceRecords will be created. The button intentionally doesn't override existing AttendanceRecords so that manually overridden records don't get deleted, but it should be safe to change records from present=false to present=true.
Currently, the "Create final attendance records" only creates AttendanceRecords if none exist. If the button is clicked before all RawAttendanceRecords have been uploaded, then incorrect AttendanceRecords will be created. The button intentionally doesn't override existing AttendanceRecords so that manually overridden records don't get deleted, but it should be safe to change records from present=false to present=true.