An unreleased 12.2-inch Lenovo Yoga Book has shown up on Amazon recently, and while the listing is still active the tablet is showing up as out of stock. The larger Yoga Book has not officially been announced by Lenovo yet so it makes sense that it wouldn't be for sale, and it's likely that the listing may just be a place holder for now, considering that the images are no longer available on the listing page and that the price is $299, which is a significantly less expensive amount compared to the original Lenovo Yoga Book which launched last year. That model, which came with a 10-inch screen and was priced at $499, so it's not likely that the a larger version would come in cheaper.
According to the specifications details this version of the Yoga Book runs on Android 6.0.1 Marshmallow which is the same version of Android on the currently available model, and it's powered by an unspecified Intel processor although it does mention that it's four cores. Having said that, Tablet Monkeys states that the processor is an Intel Atom x5-Z8550 which is the same CPU used in the 10-inch model. The 12.2-inch screen is listed with a resolution of 1280 x 800 and it weighs 2.2 pounds, it comes with 2GB of RAM, and it has an internal storage of 128GB. It's also said to come with a battery life of around 15 hours thanks to the 10,500mAh battery inside.
While none of these specs are really anything more than standard, one detail that sets this tablet apart from the older model besides the bigger display is that the listing states it runs on a modified version of Android that comes pre-installed with a Google productivity suite, and it features a taskbar that shows your open apps which can be rearranged in any order. The taskbar is not something that stock Android offers natively, but you will find it on other custom versions of Android like Remix OS. The listing doesn't mention that this model of the Yoga Book is waterproof, but one image of the tablet shows that it is. It also apparently comes with a USB Type-C port in addition to one USB 2.0 port, and it supports Bluetooth 4.1 and GLONASS as well as Wi-Fi 802.11a/b/g/n. There's no release date just yet since it hasn't formally been announced, but when it does launch it will be available in both a Gunmetal Grey and a Pink color.