First Log, Last Log simply means that the system does not need to see whether the employee’s logs has any flagging. It will automatically just get the earliest log and set it as IN. The latest log will be set as OUT.
Every in and out is very particular about the flagging. There must be a flag for the system to recognize the employee as working or not. Incorrect data such as 8am out and 5pm out will yield as 8 hours undertime because no IN log was present.
This configuration also calculate the break hours.
