(Image credit: Tom's Guide) The long-rumored AirPods Ultra may already be in the later stages of development, meaning their release might be sooner than we initially thought. According to sources speaking to Bloomberg , development has now entered a phase featuring prototypes with "near-final design and capabilities." Sources say that testers within Apple are actively using prototypes of the new AirPods, as part of what's known as design validation testing (DVT). This is the final stage of the development phase, and once complete Apple will start a production validation test (PVT). That's when the sample units of the final design are built, ahead of full-scale mass production. What we know about AirPods Ultra (Image credit: Tom's Guide) The AirPods Ultra will reportedly have a design that's siimilar to the AirPods Pro 3 but with a number of important enhancements.…