Some Apple Genius Bars Replacing iPhone 4 with iPhone 4S Shawn Ingram05/07/2012 Thanks to a shortage of iPhone 4 units some users are finding their broken iPhone 4 replaced with an iPhone 4S at Apple Store Genius Bars. According to 9To5Mac, supply constraints at some Apple Stores, Genius Bars are replacing broken iPhone 4 units with iPhone 4S units of the same capacity and color.Advertisement In mid-April Genius Bars were replacing the 16GB white GSM (AT&T) iPhone 4 units with refurbished iPhone 4S units because the company didn’t have the replacement iPhone 4 devices on hand. Apple has since caught up with on white 16GB GSM iPhone 4 units, but now is facing short supply of black 16GB iPhone 4 and black 32GB iPhone 4 units. It’s not clear if the limited supply is for AT&T or Verizon units, however. Genius Bars that don’t have enough units for replacements are replacing them with iPhone 4S units. Advertisement Not all stores have supply constraints. Some Apple Stores still have enough iPhone 4 units on hand for replacements. So some users will walk away from the Genius Bar with an iPhone 4S in exchange for their broken iPhone 4, but not everyone. There’s no way to check which Apple Store has supply constraints, as an unexpected upgrade for a broken iPhone 4 isn’t exactly the sort of program Apple would want to publicize.Advertisement If April’s supply constraints are any indication, Apple should have more black 16GB and 32GB iPhone 4 units sometime within the next few weeks. Until Apple stores receive more units, don’t be surprised to hear a few stories of iPhone users turning in their broken iPhone 4 and walking away with a Siri-equipped iPhone 4S.