Verizon and AT&T aren't the only service providers preparing for the iPhone 5 release date, which is rumored to come next month. T-Mobile has also sent out memos to its employees to prepare for what may be the largest handset launch in mobile history.

But unlike its rivals, T-Mobile is advising its staff to prepare to sell "against the iPhone," according to internal company documents discovered by TmoNews. Based on this allegedly leaked information, it may be safe to say that T-Mobile will not be carrying the iPhone 5 when its purported release date arrives.

One section of the September Training Priorities paperwork contains a section called "Selling Against the iPhone." The document says that on Sept. 21, the date that the next iPhone is rumored to be made available, a "Grab & Go" mobile packet will be available for T-Mobile employees. It is unclear exactly what this means, but the memo says that employees can find this "Grab & Go" information in a new "Competitive Resources space" that will be available on Sept. 5.

The document does not explicitly say what its tactics are for "selling against the iPhone," but the "Grab & Go" package is likely to be a training tool for employees to combat highly competitive iPhone sales.

The other bit of information revealed in the documents says that T-Mobile will be offering new monthly 4G Micro SIM Kits beginning this Wednesday. These are kits that will be compatible with Apple's iPhone 4 and iPhone 4S that will be offer 4G connectivity, since T-Mobile doesn't provide the LTE network that is likely to be needed for the iPhone 5.

T-Mobile users will be able to bring their unlocked iPhones to a retail location and pick up a 4G Micro SIM Kit, which seems like an attempt to keep customers from switching to other carriers to purchase the iPhone 5.

This allegedly leaked paperwork is just another bit of evidence that Apple's iPhone 5 will see a release date next month. Earlier this week, a Verizon executive reportedly told Tech Crunch that an all-staff vacation blackout would occur from Sept. 21 through Sept. 30. The technology news source reported that this was a clear indication that the iPhone 5 would launch near or during that period.

"It stands to reason that Verizon would want as many retail staffers on hand as possible for the launch of arguably the most eagerly anticipated gadget of all time," writes Jason D. O'Grady of ZDNet.

Earlier in August, BGR reported that a "trusted AT&T source" said that the service carrier was planning to release the next-generation iPhone during the third or fourth week of September.

T-Mobile isn't the only company taking precautions to battle what is expected to be record breaking sales of Apple's iPhone 5. It was reported earlier in August that Samsung will compensate any user who sends in a used smartphone, including iPhones, and purchases any Samsung smartphone. Those who send in a perfect condition iPhone 4S 64GB will receive a rebate of $300, according to Samsung. The 32GB variation of the iPhone 4S will sell for $230 and those turning in the 16GB edition will receive $215.

With the release date for Apple's iPhone 5 allegedly coming soon, numerous reported leaks and rumors have flooded the Internet within the past two months. One of the most recent speculations came on Monday when a photo that was said to be the completely assembled front plate of the iPhone 5 surfaced. A Near Field Communication chip was believed to have been spotted near the device's camera, but reports that have been published on Tuesday indicate that the iPhone 5 will not support NFC connectivity.

"Given the primarily metal backside of the new iPhone, it's highly unlikely that NFC is in the cards for this generation," AnandTech reported. "In fact, given the very little space at top and bottom dedicated to those glass RF windows, you can almost entirely rule it out."

The iPhone 5 is rumored to come equipped with a ton of other features as well, including a longer 4-inch display, tougher glass, a new smaller dock connector, OLED display, in-cell touch panels, and new abilities that will be included in iOS 6 such as the Passbook. Users will have to wait until next month to see if Apple truly announces its next-generation iPhone 5.