This may sound like an odd question, but if I activate my iPhone 4 tomorrow, will I still be able to use AppleCare on my 3G (expires end of July)? In other words, if the 3G is not in service, can it still be repaired/replaced under warrantee? I ask because I want to sell my 3G and there's a bit of dust under the screen. I've heard that Apple will replace an iPhone with dust for a refurb. I'd appreciate any feedback.