We already know that next week’s September 12th Apple (AAPL) event will bring the announcement of the iPhone 5, but rumor has it the 8GB iPhone 3GS will finally be retired. The Telegraph reports that sources close to retailers say Apple will replace the entry-level iPhone 3GS with the 8GB iPhone 4 and a new 8GB iPhone 4S to its lineup. Essentially, the 8GB iPhone 4 will be offered free on contract as the 3GS has been, and the 8GB iPhone 4S will become a new mid-point offering. Naturally, the new iPhone 5 will sit at the top of the totem pole and will come in capacities of 16GB , 32GB and 64GB. It can be argued that the 3GS has been a boon in emerging markets, especially because Apple will continue to support it in iOS 6, but we think it’s time to let the three-year-old device go. After all, it is the only iPhone that still doesn’t support Retina display apps.