Though iPhone shipments could fall under Wall Street consensus for the December quarter, Apple's revenue from the product should be boosted by high consumer favor for Plus models, an analyst noted on Tuesday.

A recent Consumer Intelligence Research Partners survey in the U.S. found that Plus models represented 42 percent of iPhone sales, up from 26 percent a year ago, according to memo by UBS analyst Steven Milunovich, obtained by AppleInsider. The Plus is the only version of the iPhone 7 with a dual-lens camera, offering optical zoom for the first time on an iPhone, along with a special Portrait mode simulating blurred backgrounds.

The CIRP also found that 62 percent of people were choosing to pay extra for storage upgrades, which along with the Plus preference could push Apple's average selling price (ASP) higher. UBS's target is $693, higher than the consensus $685.

This means that despite the firm forecasting 76 million in global iPhone sales versus a consensus 78 million, UBS is calling for $77.8 billion in revenue, higher than the Street's $77.4 billion, and at the upper end of Apple's own guidance between $76 billion and $78 billion.

Other aids to Apple are said to include "stable" Android switching figures, and no apparent stretching in replacement cycles. Indeed CIRP said that 54 percent of people in the December quarter had phones that were two years old or less, up from 49 percent in 2014.

UBS has set a "buy" rating for Apple stock, with a $127 price target. The firm is downgrading its iPhone shipment predictions for the upcoming March and June quarters — from 55 million to 52 million, and from 44 million to 42 million, respectively — but suggests that this may not matter if investors stay optimistic about Apple's new financial year.