Mukesh Ambani-led Reliance Jio Infocomm can’t offer promotional offer beyond December 3, 2016. Sector regulator Telecom Regulatory Authority of India (Trai) said in a letter to all other GSM telecom operators. The new 4G entrant Reliance Jio kicked off its commercial services on September 5 with the launch of the free promotional offer, namely “Welcome Offer”, which the company has said will provide free access to voice service and data till December 31, 2016.  Jio 4G free service validity Trai said that deliberations held on September 30, following a joint representation dated September 20 against Jio’s violation TTO provision by other telecom operators. It said that Reliance Jio had filed…