T-Mobile, the third-largest wireless carrier, said a smaller portion of its customers upgraded their phones in the third quarter—just 6% compared to 7% last year. In 2017, the carrier was selling the iPhone 8 but obviously not the X model, which hits stores Nov. 3. In contrast, last year Apple introduced only the iPhone 7 line and it went on sale in mid-September.

“Device sales and upgrade rates were impacted by the split and shift in iPhone launch timing,” T-Mobile said in a statement. “We believe these will likely increase once customers have a full choice of devices.”

The news came as T-Mobile reported strong third quarter results, with revenue increasing 8% to $10 billion and earnings per share up 50% to 63 cents. But T-Mobile (TMUS) decided not to have a call with analysts, as it feared being swamped by questions about its rumored merger with Sprint.

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The iPhone sales slowdown was similar to the experience of Verizon (VZ), the largest wireless carrier, which said last week that the upgrade rate of its customers had also slowed. And Verizon, too, expects a big pick up from the iPhone X next month, CFO Matt Ellis said. “As we get into the holiday season, some of those new devices come out, we think we’ll see strong demand,” Ellis said. Sprint (S) and AT&T (T) have yet to report their third quarter results.

A study by Consumer Intelligence Research Partners also found that demand for the iPhone 8 trailed both the iPhone 6 line and 6S when they were issued as new models over the past two years.

Apple (AAPL) shares have been under pressure due to the weak iPhone 8 sales indications. The stock lost 2% since Verizon’s report, amid rumors that the company asked its iPhone suppliers to cut back on production of the 8 models.