Ahead of Apple's big keynote on Wednesday, new details have leaked out to give us a more accurate picture of its upcoming iPad Pro. According to several sources, the device will pack a "monster display," but we'll have to wait until November to get one.

"While Apple still plans to announce the device this week, open up pre-orders in October, and begin shipping in November, we understand that the first shipments may fall towards the end of November," reports 9to5Mac.

The reason for the somewhat scattered launch is that production of Apple's brand new tablet is still behind schedule. So behind, in fact, that even after the device starts shipping in late November, initial supplies are expected to be very constrained.

That means it's going to be difficult to get your hands on the iPad Pro initially, even though it's likely to cost a lot more than the smaller iPad Air 2. But of course, it will be worth the wait — and the added cost.

According to 9to5's sources, the iPad Pro will sport a 12.9-inch "monster display" with a split-screen multitasking mode that allows two full-size iPad apps to sit alongside each other in portrait mode when looking at the screen in landscape.

In contrast, iOS 9's Split View mode on the iPad Air 2 condenses portrait apps so that it can fit two of them onscreen, and they'll be condensed even further on the upcoming iPad mini 4, which is also expected to get Split View multitasking.

The iPad Pro will reportedly be powered by Apple's brand new A9X processor, which "we've heard will be a "large" leap over the Air 2's A8X," 9to5 adds. The device will also have four stereo speakers on its top and bottom edges, but only one Lightning connector.

Apple is also expected to ditch the 16GB storage option for the iPad Pro and make 64GB available as standard. It's thought there will also be a 128GB option for those who need it, as well as additional models with LTE connectivity.

As for the stylus and keyboard we've been hearing about a lot in recent weeks, those are going to be optional extras, sources say, so you'll have to pay more for both of them. The keyboard will reportedly be available in two models, one of which is a standalone option like the one Apple already offers, while the other is integrated into a protective case.

It's unclear whether Apple will announce all three accessories on Wednesday, but there's little doubt now that the iPad Pro will get its unveiling.