Hmm, so I have here a slight variation on previous suggestions that is my 'bet' for the reveal on 29th. To me it is inconceivable that the x could reach production without the ability to create a flat load floor. It was a feature made much of at the prototype reveal; and confirmed by email last June (above). Elon's promise was that a production Tesla vehicle will always be better than the prototype. If it looses the ability to create a flat load floor, it will be poorer than both the prototype and pretty much every vehicle that claims 'utility' in its name.
We also know that these second row seats have been an engineering challenge 'greater than the falcon wing doors' to paraphrase Elon. That the result of that effort should be fixed seats that simply move back and forward is also inconceivable.
The EV architecture gives Tesla much more freedom to design the internal arrangements... in this case, the key thing is that there is no transmission tunnel interrupting the floor. The X is also a good bit higher than the S, so the front seats will be higher, and there will be more space underneath them. So ... the front seats are I think cantilevered, with maybe 2/3 of their depth being free of any obstructions / supports underneath. This enables the rear seat to submarine underneath, as has been suggested by others. The centre console will also have space underneath it in the same fashion. The adjustable thigh supports that have been noted by others (retracting as the seat submarines) result in smaller seat pad volume, making it easier to get the seat pad underneath the front seat. The slot down the front of the second row support pedestal also suggests this is what will happen.
I think it will work something like the sketch below. After the second row submarines, the pedestals will be left protruding from the floor, behind the second row. The third row then folds FORWARD, and will be supported at the head end by the pedestals. Note that the head restraints on the third row either remove completely or fold forward. I think that when they do, it will expose the mechanical connection that will engage with the pedestals.
I'm putting £1 on this being the solution.
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