On Friday, a law firm accidentally posted a letter to the FCC website, detailing AT&T's confidential 4G LTE rollout plans and explaining how they would be bolstered by a merger with T-Mobile. Arnold & Porter LLP, which is helping design the deal on AT&T's behalf, quickly removed its partially redacted document, but the folks over at Gizmodo have gotten their hands on it once again and recently posted it for our viewing pleasure. According to the document, AT&T plans to extend its US coverage to 70 million consumers by the end of this year, before ramping that figure up to 170 million by the end of 2012 and a full 250 million by the end of the following year. The carrier plans to achieve this by upgrading a full 44,000 of its nodes to LTE over the course of the next three years and, once its merger goes through, hopes to cover 97 percent of all Americans within the six years following approval. The letter goes on to explain how the economics behind the TIA-approved deal would help facilitate these aspirations, while confirming that the merger is indeed as expensive as earlier reported -- a whopping $3.8 billion, to be exact. To read the document in full, hit up the links, below.