My company has attendance and Payroll software. If proper In-Out punches are not applied and no leave is balance then automatically it calculates LOP for those days. In this case, the basic salary is also reduced in proportion to the absent days. What if an employee during the notice period deliberately takes leaves over and above available and also misses to punch for attendance, the salary for that month gets reduced ( i.e basic changed). So for calculating Gratuity, the last working month's basic will be considered (reduced) or the basic as per the CTC. (Service rendered is more than 7 years.)