Reviewing Employment Policies
Please review your employment handbook, employment contract, and standing orders. Is there any provision for leaving early? If so, what are the terms stated there? If there is no provision, the management is free to put in a clause, but it should ideally be fair. If it is to be inserted into the Standing Orders, it needs approval from the Labour Commissioner. If it is a change in the HR Handbook, remember it amounts to a change in the Conditions of Employment, which can give rise to rights under the Industrial Dispute Act.
Many companies have a rule of not allowing an employee to leave early. In such a case, the employee will need to take half a day and leave. If it is an emergency, the manager may allow them to leave. The payroll system may not even have a provision for working seven days.
The Importance of Flexibility in Work Hours
In the current employment environment, being so hard and strict on timing does not work. You will find good people walking off (or the younger generation refusing to work for you). So, you need to convince your managers not to go down the route they have chosen.
And as Madhu-ji says, ensure that deductions do not result in a person going below the minimum wages for even that particular day.