Aadhaar authority UIDAI Chief Executive Ajay Bhushan Pandey was on Friday given additional charge as chairman of the Goods and Services Tax Network (GSTN), an official said here.

“Dr Ajay Bhushan Pande will hold charge of chairman GSTN in place of Navin Kumar who retired recently. He is DG UIDAI (Aadhar)”, Revenue Secretary Hasmukh Adhia said in a tweet. Kumar retired as Chairman GSTN in the last week of August.

“He brings with him his vast experience of implementing complex IT projects. I welcome him to the Team GST of Revenue deptt,” the Secretary said in a separate tweet.

Pandey has been associated with the Unique Identification Authority of India (UIDAI) since its launch in 2010. An officer of the Indian Administrative Service (IAS), Pandey graduated from IIT Kanpur and holds an MS and PhD in Computer Science from the University of Minnesota in the US.

GSTN has created and operates the digital network for the Goods and Services Tax (GST) that has been implemented pan-India from July 1.

The GSTN portal has been non-functional on several occasions in this period being unable to handle the rush to file returns coming closer to the deadline.

The government has extended the deadline for filing the GST sales return — GSTR-1 — which was to expire on Tuesday, for another five days till September 10.

“GIC (GST Implementation Committee) decides to extend date of GSTR 1, GSTR 2 and GSTR 3 for the month of July to 10th, 25th and 30th September 2017, respectively,” the the Central Board of Excise and Customs (CBEC) said in a tweet.

It also extended the deadline for filing GSTR 1, GSTR 2 and GSTR 3 for August to 5th, 10th and 15th October, respectively.

While GSTR-1 is the sales return and GSTR-2 is the purchase return, GSTR-3 is the match of GSTR-1 and GSTR-2.

On Monday, many Goods and Services Tax (GST) assessees had complained of being unable to log on to the GSTN portal due to the massive rush to meet the deadline for filing GSTR-1. Later in the afternoon, there were reports of the GSTN portal having crashed owing to heavy load.

Last month, the government announced a five-day extension for filing the initial GSTR-3B return till August 25, after the GST Network (GSTN) return filing portal was hit by a technical glitch and stopped functioning, a day ahead of the last date for filing.