Speculation about a 12-inch MacBook Air with a high-resolution retina display has been going on for a while. Last we heard the svelte notebook was rumored to make an appearance at next week's media event, but according to the Wall Street Journal, a ship date sometime in Q2 2015 is more likely.

The paper claims that partner manufacturers have already started mass production of the device, and will be ready to ship in large quantities next quarter. Although a specific launch schedule remains unclear, with Apple Watch coming in April as confirmed by Tim Cook himself, it's likely Cupertino will unveil the updated Air at its Worldwide Developers Conference.

Although the conference is traditionally used by Apple to showcase its new software and technologies for software developers, the company has launched hardware products during WWDC before, including most recently the Mac Pro in 2013, the Retina MacBook Pro in 2012, the iPhone 4 in 2010, among others.

Apple currently offers Retina displays on the pricier MacBook Pro range, with the 13.3-inch model offering a resolution of 2,560x1,600 pixels and the 15-inch model going up to 2,880x1,800 pixels.

A Retina MacBook Air has been a long time coming but, of course, higher-resolution displays also drain up more battery. Perhaps only now that more efficient Broadwell chips are coming out Apple's ultra thin laptop will be able to support them without battery life taking a big hit.