Deduction under sec 80C

I have LIC policy and the premium is paid Qly. The premium for the 4th Qr is due for payment in Mar 19. How can I declare this amount to the employer without a proof now. The employer is asking declaration with proof for TDS purpose. Can I show the premium due in Mar 19 without a receipt. What is the order in such cases. Declarations are asked by employers even 6 months in advance or more for TDS purpose. Thanks in advance if respected experts could guide me.