RCM QUERY IN GST

As per sub section 3 of Section 13 of CGST Act , the liability to pay on RCM arises ,
(a) Date of payment entered in Books or Debit from bank Recepient whichever is earlier
(b)Within 60 day from date of issue invoice/document by Supplier
If in above where it is not possible to determine the time of supply then the Time of supply will be the entry in the books of Recepient.

Hence in Regard to above conditions , if you fails to pay the RCM accordingly then Interest is applicable @ 18% (as per section 50 CGST )