The red-hot rumors about a Sprint iPhone loomed large during CEO Dan Hesse’s remarks at an investor conference yesterday.

Hesse stayed coy about the rumors during a talk at the Goldman Sachs 20th Annual Communacopia Conference, neither confirming nor denying the reports that Sprint would land the iconic device in October.

However, he did say that the operator’s current guidance did not include the “rumored device.”

“Theoretically, if we were to secure such a device, we would have to adjust guidance for that,” he said.

The iPhone has been “the number one reason customers churn,” Hesse said, emphasizing that Sprint has been able to weather competition on the device from AT&T and Verizon Wireless fairly well despite its popularity. 

Hesse also talked about the longevity of Sprint’s unlimited plans. Sprint has used its all-you-can-eat plans to set itself apart from its larger competitors, but it’s not clear how long it can profitably offer the plans amid soaring data use – especially if it lands the bandwidth-hungry iPhone.

The plans will only be offered as long as they maintain the bottom line, Hesse said.

“It if becomes unprofitable, we won’t offer it anymore,” he said. “We work on all sorts of initiatives across the company to try and maintain that.”

The DOJ’s antitrust complaint against AT&T’s merger with T-Mobile USA also came up. Hesse said he didn’t see the suit as a sign that the DOJ was opposed to further consolidation in the wireless industry.

“My view is they’ll look at other consolidation differently,” he said.

Sprint had considered a merger with T-Mobile but lost out to AT&T. It is not clear whether Sprint would again pursue T-Mobile if the AT&T deal fell through.