GSTR 3B

If Input tax credit is available under VAT and this month under GST tax is liable to be paid, then should we have to pay GST this month? or file GSTR3B and Trans1 by 28.08.17.

If Input tax credit is available under VAT and this month under GST tax is liable to be paid, then should we have to pay GST this month? or file GSTR3B and Trans1 by 28.08.17.