Other industry observers, however, believe the credit scores are being affected by T-mobiles push into its pre-paid service, Flex Pay. Andy Zeinfeld, CEO of Simplexity, which runs online mobile phone retailer Wirefly.com, said that credit scores were being blended down because of the pre-paid service, but that it did not amount to a “material change.” There’s also the argument that T-Mobile is pursuing a younger customer, who may not necessarily have a poor credit history, but an incomplete or non-existent one.

As Dow Jones (NYSE: NWS) also points out T-Mobile doesn’t have the myriad problems Sprint did, when its loosening of credit standards sent its churn rate shooting up, but it is facing a lot of competition to grow. Its being squeezed in the middle, as high-end customers tend to go to Verizon (NYSE: VZ) or AT&T (NYSE: T), and pre-paid customers tend to seek out pre-paid players such as MetroPCS and Leap Wireless, with their enticing cheaper unlimited plans.