ITC Availment if RCM Supplier Late Submit GSTR-1

For Example : Return Period January :-  RCM Supplier has Late Submitted GSTR-1 on February 20th 

 Effect on Recipient GSTR-3B -- Not Reflected RCM Liabilities for  January . But it will Reflect on February

( Kindly Note :  RCM Invoice already Received by Recipient on  January )

Question: 1) In  Which Month Can Pay RCM Liabilities by Recipient --- January or February 

                 2) In Which Month Can Avail ITC by Recipient  -- January or February