When Microsoft first announced the Surface Pro 2 alongside the cheaper Surface 2, it promised the Windows 8.1 tablet would launch on Oct. 22, but now it looks like the company has been forced to push back the release date for high-capacity versions of the device. The Microsoft Store website now lists the shipping date for both the 256GB and 512GB Surface Pro 2 models as Dec. 15. Meanwhile, the 64GB Surface Pro 2 ($899) is set to ship on Oct. 21, while the 128GB model ($999) won’t ship until Oct. 25.

Microsoft hasn’t released a statement regarding the delayed shipping dates for the 256GB and 512GB Surface Pro 2 models—priced at $1,299 and $1,799, respectively. However, it seems likely the company manufactured a limited number of these high-end models, and now is facing unexpected interest in the upcoming tablets.

The Surface Pro 2 comes equipped with a 10.6-inch 1920 x 1080-pixel display at 208ppi, an Intel Core i5 processor clocked at 1.6GHz, expandable storage via microSD slot, rear and front-facing 720p cameras, and a 42 W-h battery. You can check out our hands on impressions of Microsoft’s new tablet now, and stay tuned for our full review.