Dear Sonia,
Section 192 reads as under:
192. 58(1) Any person responsible for paying any income chargeable under the head Salaries shall, at the time of payment, deduct income-tax 59[***] on the amount payable at the average rate of income-tax 60[***] computed on the basis of the 61[rates in force] for the financial year in which the payment is made, on the estimated income of the assessee under this head for that financial year.
Now income under head salary is taxable on receipt basis or accrual basis whichever is earlier. Hence advance salary is also taxable on receipt basis even though it has not accrued. Since TDS is payable at the time of payment of salary, TDS must be deducted from Advance salary also.
Regards,
Chintan