After nine straight quarters of decline, Airtel's Arpu rose to Rs 104 in the October-December period of FY2019 from Rs 100 in the preceding quarter (Q2). This more than offset the loss in decline in subscribers, Citi Research said in a note. The 4G subscriber additions stood at 11 million versus 7 million in Q2, with the 4G subscriber base at 77 million, which is 27% of total user base in the third quarter versus 20% in second quarter.

Analysts at Jeffries said for Airtel, less than 50% of low Arpu subscribers upgraded to the minimum recharge plan. All this while, the data subscribers and usage increased sharply. The data usage per user increased to 10.5GB in third quarter versus 9.2GB in Q2, and is now almost at par with Jio's 10.8GB.

For Vodafone Idea, the 4G subscriber base moved up to 9.5 million in the third quarter from 8.4 million in the second quarter. However, the company's 4G user addition was lower compared to around 11 million for Bharti in Q3. Arpu improved marginally to Rs 89 from Rs 88 a quarter ago.

"There was subscribers clean up, without a significant improvement in Arpu for Vodafone," Bank of America Merill Lynch said in an analyst note.

The telecom sector has been reeling under financial constraints since the entry of Reliance Jio. The shock waves are still being felt even after over two years of Jio's entry. In Q3 FY2019 a single quarter, Vodafone Idea posted a loss of about Rs 5,005 crore, Airtel posted a 72% decline in profits and Reliance Communications knocked at the doors of NCLT for insolvency, second telecom firm to do so in recent times.

Though weeding out low Arpu users could help telcos in improving their profitability, the real shift will come only with the tariffs revision, according to experts. Apart from minimum recharge plans, telcos have harmonised their prepaid and postpaid offerings with bundled offers, which is driving data usage and is expected to improve revenues further.

"While Bharti (Airtel) is better positioned than incumbents, recovery is still some time away. The key for Bharti going forward is the improvement in pricing, which still remains elusive. Jio has indicated that it does not feel a need to change Arpu currently. We expect competitive intensity in India business - mobile, home and enterprise to remain high over the next six-nine months. Further, investments in network and add-on services to continue which will partly offset cost rationalisations," an analysts at Jefferies said.

A BNP Paribas analyst also echoed similar views. "We expect Airtel to start seeing quarter-on-quarter revenue growth even in the absence of tariff hikes on rising adoption of data bundles. Tariff hike remains key driver for the sector, which is a matter of time as at current tariffs, operators are unlikely to derive reasonable returns on their investments."

It remains to be seen when will such measures, taken by operators to drive 4G services, actually create sustainable long-term earnings.