Apple Inc.’s basic iPhone 15 model is taking almost twice as long for deliveries this year than its predecessor, signaling high demand for the company’s latest handsets.

In China, Apple’s biggest overseas market, wait times for the iPhone 15 have quadrupled, according to data from Counterpoint Research. At the other end of the spectrum, Apple’s top-tier iPhone 15 Pro Max also increased pre-order waiting times to a record, the researchers found. Significant upgrades to both models drove renewed demand, though some of it came at the cost of Apple’s other options, the 15 Plus and 15 Pro, which both saw diminished wait times.

“We were expecting the base model iPhone 15 wait times in China to come in a lot lower – maybe on par with last year,” said Archie Zhang, an analyst at Counterpoint. “And as far as ultra-premium is concerned, the Pro Max is still the most coveted iPhone in China with long delivery wait times reflecting this.”

The extended delivery times haven’t translated to elevated resale prices, as the researchers affirmed reporting from Bloomberg on Friday that scalper prices in China command only moderate premiums. That may indicate demand is driven at least in part by people trading in their existing devices.

“In a year marked by declining smartphone demand, the trade-in program is expected to play a pivotal role in reducing psychological barriers for those contemplating a new phone purchase,” said Counterpoint’s Ivan Lam. “It’s becoming an increasingly vital contributor to Apple’s market dominance.”

Read more: Scalpers, Apple Fanboys Vie for Latest iPhone Despite China Ban

--With assistance from Debby Wu.