Nokia is set to announce an oversized Windows Phone tomorrow and we already know plenty of details thanks to a handful of leaks. If you need further evidence or will be busy with Apple news on October 22, however, the latest tidbit comes courtesy of the company's official Tmall store in China, which mistakenly published details on the Lumia 1520 ahead of its announcement -- and it pretty much confirms what we’ve been hearing.

Specifications for the device are said to include a 6-inch 1080p display, a quad-core Qualcomm Snapdragon 800 processor, and a 20-megapixel PureView camera. With this Nokia and Windows Phone will venture into phablet territory for the first time thanks to a new version of Microsoft’s mobile platform (Windows Phone 8 GDR3) that adds support for larger and higher density displays, among other things.

Official details about the upcoming Windows Phone update were made public last week.

Nokia is gearing up to announce a range of devices tomorrow at its Nokia World event in Abu Dhabi. Aside from the Lumia 1520, the company is also expected to introduce a 10.1-inch Windows RT tablet, dubbed Lumia 2520.

Thought vastly surpassed by Android and iOS, Microsoft's Windows Phone has secured the third spot among all mobile operating systems, and much of it is due to Nokia’s devices. The Finnish firm is seeing slow but steady growth and according to Wall Street Journal’s estimates it is set to hit a record high for the fourth consecutive quarter. In particular, the paper believes Nokia sold "at least eight million" Windows Phones between July and September, which is close to triple the 2.9 million sales it managed in the same period last year.