The GST department published a Press Release on October 21st, 2018 to notify the extension of the due date for furnishing return in form GSTR-3B for September, 2018 to 25th October, 2018. The previous date for the same was 20th October, 2018. This move is meant for the taxpayers to rightfully claim their Input Tax Credit for the period July, 2017 to March, 2018. As per the GST law, the last date for claiming ITC for the said period was the last date for filing of return in GSTR-3B for September, 2018. The extension from 20th to 25th of October, 2018 provides taxpayers with the option to file returns and claim ITC if they had missed out on doing so by the previous deadline.
Here is the Press Release issued by CBIC for your reference: