iPad Pro cover leak shows opening for rumored new Smart Connector location
A supposed leak has surfaced, showing a new case allegedly designed for refreshed iPad Pro models, with the internal shots of the plain case appearing to have a new cut-out on one side that could be used for the rumored relocated Smart Connector.

Via Slashleaks
Two similar photographs published by Slashleaks show a large rear cover, most likely produced from plastic, that contains all of the openings on the edges for the assorted buttons and other elements that appear on the sides of an iPad. Along with the other holes is an extra opening, located near to where the Lightning port at the base.
The oval opening isn't explained in the leak, but its shape, size, and position appears to line up with an earlier leaked CAD image from July. The supposed render of the refreshed iPad Pro showed an identical pill-like shape in close proximity to the Lightning port, slightly recessed from the surface, with little explanation for what it was.

Via Slashleaks
Another report in the same month claimed the Smart Connector would be moved from its current location on the side of the iPad Pro to the "lower rear side," close to the Lightning connector.
It is unknown if today's leak is genuine, as it pertains to an accessory for the device rather than the device itself. While accessory producers can sometimes get tipped off about designs by device producers ahead of a release, it is also possible that the case vendor who produced the cover relied on earlier leaks about this mystery connector.
Additionally, the existing Smart Connector is a surface mount, with nearly no ability for a keyboard to connect to it, given the thickness of a protective case. If this case is accurate, there would have to be some redesigns to the spec or connectors to allow for that gap that would be induced by the case material.
Expected to ship sometime this fall, the 2018 iPad Pro models are speculated to have a smaller footprint but retain the screen size, bringing it closer to an iPhone X with an edge-to-edge display. Touch ID would be removed in favor ofFace IDand the screen notch, as well as suggestions it would also eliminate the headphone jack.

Via Slashleaks
Two similar photographs published by Slashleaks show a large rear cover, most likely produced from plastic, that contains all of the openings on the edges for the assorted buttons and other elements that appear on the sides of an iPad. Along with the other holes is an extra opening, located near to where the Lightning port at the base.
The oval opening isn't explained in the leak, but its shape, size, and position appears to line up with an earlier leaked CAD image from July. The supposed render of the refreshed iPad Pro showed an identical pill-like shape in close proximity to the Lightning port, slightly recessed from the surface, with little explanation for what it was.

Via Slashleaks
Another report in the same month claimed the Smart Connector would be moved from its current location on the side of the iPad Pro to the "lower rear side," close to the Lightning connector.
It is unknown if today's leak is genuine, as it pertains to an accessory for the device rather than the device itself. While accessory producers can sometimes get tipped off about designs by device producers ahead of a release, it is also possible that the case vendor who produced the cover relied on earlier leaks about this mystery connector.
Additionally, the existing Smart Connector is a surface mount, with nearly no ability for a keyboard to connect to it, given the thickness of a protective case. If this case is accurate, there would have to be some redesigns to the spec or connectors to allow for that gap that would be induced by the case material.
Expected to ship sometime this fall, the 2018 iPad Pro models are speculated to have a smaller footprint but retain the screen size, bringing it closer to an iPhone X with an edge-to-edge display. Touch ID would be removed in favor ofFace IDand the screen notch, as well as suggestions it would also eliminate the headphone jack.
Comments
Edit: Nevermind I was totally wrong, the hole is on the opposite side of where the Smart Connector is on the current gen iPP. Now I wonder what that hole is for...
I had an original iPad and had to look up a pic to see that it's edges/sides were indeed flat. That reminded me that I was disappointed in the tapered edges because it made plugging in the 30-pin dock connector slightly awkward.
The tapered edges on a large display, as in the iMac, are a nice styling touch. But for a phone or iPad, I'd prefer flat edges/sides. And yes, that could mean more battery, always a good thing.
Implementing this on the iPad creates a problem in that sometimes we use the device when it's stationary, for example, when it's being used with the SmartKeyboard or any other keyboard, or when it's otherwise set up on a table or desk with a smart cover propping it up. Is Apple going to force us to pick up the iPad to wake it up/unlock it when we already have it set up like that. No, they are probably going to build in a way to trigger FaceID that doesn't require lifting the iPad. The On/Off button could handle this functionality, but that sometimes results in an expenditure of force sufficient to dislodge the iPad from its cover/keyboard. So how about a touch sensor that allows you to flick a finger across to trigger FaceID to do its thing. Maybe they would place such a sensor on the back right by the location that used to house the Home Button, as muscle memory has trained us to place our hand on that spot to use TouchID, except in this instance we'll be using our forefinger or middle finger on the back, rather than our thumb on the front.
If that opening size and shape is accurate, the pill shaped hole would likely be for a Touch ID. Some people think it is where the Smart Connector would be, but that makes no sense since it is a non-edge location, and the size of the feature is much too large.
Also, a cover with a hole for a Smart Connector wouldn't work because the thickness of the cover would keep the contacts of the Smart Connector from touching the contacts on keyboard with a Smart Connector. AND the keyboard would need some sort of awkward flap with a tab on it just to get its Smart Connector in the right position... Apple would not design something like that!