GST QRMP QUERY

If QRMP scheme is opted by the registered person, for paying the tax in first two month of quarter if Self Assessment Method (SAM) is choosed, monthly payment is on net liability basis( output - input as per GSTR 2B), then my doubt is about we can consider the provisional itc for first two month tax payment? Or it is calculated only at the time of filing the GSTR 3B quarter end?