The upcoming 4G spectrum auctions are more critical for Reliance Jio Infocomm than for its rivals, Bharti Airtel NSE 1.57% and Vodafone Idea.That's since a sizable chunk of Reliance Communications 4G airwaves in the coveted 800 Mhz band—that the Mukesh Ambani-led telco uses under a sharing pact—will expire in 18 circles in July-August 2021Bharti Airtel and Vodafone Idea will also need to buy back their expiring airwaves in eight circles each, but mostly in the less expensive 1800 MHz band, also used for 4G.The Mukesh Ambani led telecom operator, Reliance Jio has been in the industry for three years now, and in these three years, the telco has amassed a massive number of subscribers beyond 300 million and brought various changes to the industry given its pricing tactics. However, all of this has been based on Reliance Jio’s success with a 4G only network.The telecom operator is the only one in the country which boasts of the “4G only” title, and it has done a good job of attracting subscribers with the 4G high data speeds and better services. But, all of this has been possible because Reliance Jio has been using 4G spectrum, and in the upcoming auctions as well, the telco awaits the sale of the 4G auction eagerly.Such a scenario leaves Jio facing a similar situation that Bharti Airtel, erstwhile Vodafone India and Idea Cellular (now merged into Vodafone Idea) had found themselves in during the February 2014 and March 2015 auctions when they had to buy back their own expiring spectrum in the 900 Mhz band in several circles at exorbitant rates, or else risked losing the mobility business, a development that has contributed to their current high debt levels, and financial stress.Reliance Jio currently uses RCom’s airwaves in 18 circles and out of these 18 circles, airwaves in 17 circles will expire in July 2021, and one more circle will lapse in August 2021. Reliance Jio holds 49 units of spectrum across these circles, and in the upcoming auctions, around 59 units of such spectrum would be put on sale.Now although Reliance Jio has airwaves in the 1800 MHz and 2300 MHz spectrum in all 22 circles, the 800 MHz is a premium band which is the most efficient for 4G use as per the experts. This is the reason why Reliance Jio is in for the early auction of airwaves because it needs to keep up with the growing demand for data services and also to cater to higher coverage.