Based on some observations, Verizon has started using its last 10 MHz of PCS spectrum in New York City for its LTE service, which BTIG analyst Walter Piecyk said is nine months earlier than the Wall Street research firm expected.

“Their accelerated use of spectrum for LTE over the past four years comes as wireless data growth rates are accelerating, despite the larger numbers,” Piecyk wrote in a blog post this morning. “This latest action also means that the only spectrum Verizon has left to convert to LTE in NYC is the 25 MHz of 800 MHz spectrum.”

BTIG noted that the data on Verizon’s spectrum usage in New York City stems from twitter user Milan Milanovic at @milanmilanovic.

FREE DAILY NEWSLETTER Like this story? Subscribe to FierceWireless! The Wireless industry is an ever-changing world where big ideas come along daily. Our subscribers rely on FierceWireless as their must-read source for the latest news, analysis and data on this increasingly competitive marketplace. Sign up today to get wireless news and updates delivered to your inbox and read on the go. SUBSCRIBE NOW

As Piecyk noted, Verizon for years has been turning on LTE services in additional bands of spectrum in New York City. Specifically, he said that Verizon launched its LTE service in 2010 on 20 MHz of 700 MHz spectrum, and in 2013 added 40 MHz of AWS spectrum to that network. Verizon began switching its PCS spectrum from its CDMA service to its LTE service in 2014—and now the carrier appears to have largely finished that PCS spectrum refarming effort.

Verizon has made no secret of its efforts to refarm spectrum for its LTE network. “We are committed to remain in the largest and most reliable 4G network through technological developments in LTE, deploying small cells and refarming mid-band spectrum,” Verizon’s CFO Matt Ellis said during the carrier’s first-quarter conference call, according to a Seeking Alpha transcript of the event. But those refarming efforts are worth watching as a possible indication of Verizon’s overall network capacity situation.

Indeed, recent research from network testing company OpenSignal indicates that download speeds provided by Verizon and AT&T have shown a “marked decline” since they each launched unlimited data plans. (To be clear, Verizon has largely rejected those findings, arguing that "isolated speed peaks from a crowd-source test don't tell the whole story.")

Nonetheless, BTIG’s Piecyk wrote that the firm expects Verizon to begin to convert its last 20 MHz chunk of CDMA spectrum, in the 850 MHz band, into LTE by end of next year. “In the meantime, we expect Verizon to attempt to accelerate its small cell densification plans as an alternative capacity solution,” he wrote.

In response to questions from FierceWireless on the topic, Verizon in a statement said that "20 MHz is a ton of spectrum. We feel good about our spectrum position, our use of LTE Unlicensed spectrum, and our densification plans through small cells and our in-building deployments. We are also aggressively refarming spectrum, since the vast majority of customer usage is on our LTE network," the carrier said. "We continue to deploy LTE Advanced features to continue to expand our capacity to provide our customers with the best network experience in the industry. Our network continues to perform extremely well nationally, and in the New York market. We recently were ranked #1 there again, by RootMetrics, for overall performance, speed, and reliability."

In his post, BTIG's Piecyk did note though that the firm expects Verizon to retain at least a small portion of its spectrum holdings for CDMA for the foreseeable future. That dovetails with Verizon’s stated intent to keep its CDMA 1X operating until at least Dec. 31, 2019 – the carrier added that it would work with its current CDMA 1X customers and would consider operating its CDMA 1X network into 2020 if those customers need more time to move onto Verizon's LTE network.

Still, Piecyk speculated that Verizon could well turn to additional sources of spectrum in order to support additional LTE network traffic. The analyst noted that Dish owns fully 125 MHz of vacant spectrum in New York, but that “Verizon will continue to claim they don’t need it.”

To be clear, this isn’t the first time that Wall Street analysts have fretted over the state of Verizon’s network capacity. More than two years ago, the analysts at New Street Research said that Verizon would run out of capacity by either 2017 or 2018—even if it refarms all its 2G and 3G spectrum.

That does not appear to have happened. In fact, in the interim, Verizon did not purchase any additional spectrum during the FCC’s recent 600 MHz spectrum auction, potentially reflecting the carrier’s efforts to densify its network through small cells and other techniques.

Article updated Aug. 7 with comment from Verizon.