The delayed launch of HTC’s new flagship phone was obviously going to be a huge problem for the vendor, and now it looks as though the HTC One might only have a week at AT&T before the Samsung marketing machine looks to swoop in an steamroll it. Engadget reports that tentative launch dates have been set according to a leaked internal document from nationwide retailer Staples, which points to an April 26th launch for the flagship Galaxy S4 smartphone at AT&T. The document also pegs May 1st as the Galaxy S4’s tentative launch date at T-Mobile, and Verizon Wireless seemingly plans to release the phone a month later on May 30th. The U.S. version of Samsung’s Galaxy S4 features a 5-inch Super AMOLED display with full HD 1080p resolution, a quad-core processor, 2GB of RAM, up to 64GB of internal storage and Android 4.2 Jelly Bean. An image of the purported leaked Staples document follows below.