(i) In terms of the extant regulations, remittances against imports should be completed not later than six months from the date of shipment, except in cases where amounts are withheld towards guarantee of performance, etc.
(ii) AD banks may permit settlement of import dues delayed due to disputes, financial difficulties, etc. Interest in respect of such delayed payments may be permitted in terms of the directions in para 2 of Part III below.
Physical import of goods into India is made within six months (three years in case of capital goods) from the date of remittance and the importer gives an undertaking to furnish documentary evidence of import within fifteen days from the close of the relevant period.
(iv). In the event of non-import of goods, AD bank should ensure that the amount of advance remittance is repatriated to India or is utilised for any other purposes for which release of exchange is permissible under the FEMA, Rules or Regulations made there under.
for more information link is:
https://rbi.org.in/commonman/English/Scripts/Notification.aspx?Id=301