You'd have thought by now that the crankshaft issue would have been sorted, I mean it's not like crankshafts are a new idea, is it.
When I looked into this extensively a few years back, I appeared that the failure was possibly down to cranks made in one factory (apparently they are made in France, by several small manufacturing contractors), one of which wasn't giving the correct heat treatment to the crankshafts they made.
How accurate this is I don't know, but it must be something along those lines, due to the randomness of the failures.
Another theory was the main bearings were turning in the block, which then blocked the oil supply to a crank pin, which would allow the pin to heat up, causing failure. There was definitely some evidence to support this, but often the tang-less bearings were blamed for rotation, but there's more to it than that.
Then delayed oil supply was suspected, likely due to the top mounted filter, but loads of other engines have top filters, which don't suffer endemic crank failure.
I have my own theories, but I'll not go into those here.
LR obviously don't know what the issue is, or simply don't care, but if loads of failures happened in the first year of the warranty, you can guarantee they'd pull out all the stops to get it sorted.