BMO Capital Markets has advised investors to refrain from buying more Apple Inc. (AAPL) stock, just hours before the Cupertino, California-based company is due to release its quarterly results.

In a research note, reported on by Barron’s, Tim Long predicted that Apple is likely to cut its guidance when it publishes its latest earnings Feb.1. The analyst, who reduced his rating on the stock from outperform to market perform, believes that an unwillingness from consumers to continue paying more for iPhones will mainly be to blame for a weaker outlook.

Long estimates that the company will post revenues of $39.9 billion in March, 12.4 percent lower than consensus expectations of $45.57 billion. "We expect a meaningful guide lower when the company reports on Thursday night, on the order of $5-6 billion compared to consensus revenue estimates,” he wrote in the note.

Like some of his Wall Street peers, Long believes that consumers are no longer willing to keep paying more for smartphones. That includes the iPhone X, Apple’s most expensive handset yet. (See also: iPhone X Orders Weakening: JPMorgan.)

“Following 10 years where average selling prices (ASPs) have generally moved higher, we believe prices will plateau as with the rest of the industry,” wrote Long. “Apple has done a good job of moving ASPs higher despite others in the industry flat-lining. We estimate that about 30 percent of iPhones will be priced over $900 this year, but we do not expect this figure to go any higher, particularly as only 12 percent of smartphones globally sell for over $600.”

Long expects these changing industry dynamics to impact Apple as early as next month. In March, he predicts that the company will move 55 million iPhones, rather than the 59.3 million units being penciled in by his peers. Long also expects the average price of the iPhone to be $726, 4 percent below consensus estimates of $756.

Looking further ahead, Long slashed his revenue and earnings estimates for the company in the fiscal year ending September from $176.88 billion and $11.34 to $161 billion and $10.46, respectively. The analyst made those cuts after predicting that Apple will sell about 9.5 million iPhones less than consensus estimates of 236.5 million.

Long also believes that revenues and earnings will come under pressure from a lack of new smartphone launches.

“We still view the iPhone base as growing, and the devices are on average getting older,” he wrote. “However, without a compelling product cycle in September, we may see a slow upgrade cycle once again. The recent stock reaction reminds us of early 2016, but later that year many investors started looking towards OLED and the 10-year anniversary phone, which drove the stock higher. No such product is on the horizon now.”

Long also identified stagnant growth in China as another bear point. “We expect no growth year over year in the China market, a reversal from last quarter’s 12 percent growth,” he wrote. "We believe China sales will be about flat in December, with units down 9 percent year/year."